Sille Van Landschoot
IBL LoRaWAN implementation
lmic.cpp
- Committer:
- mluis
- Date:
- 2015-11-26
- Revision:
- 3:519c71d29a06
- Parent:
- 1:d3b7bde3995c
- Child:
- 4:85b2b647cb64
File content as of revision 3:519c71d29a06:
/*******************************************************************************
* Copyright (c) 2014-2015 IBM Corporation.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Zurich Research Lab - initial API, implementation and documentation
*******************************************************************************/
//! \file
#include "lmic.h"
#if !defined(MINRX_SYMS)
#define MINRX_SYMS 5
#endif // !defined(MINRX_SYMS)
#define PAMBL_SYMS 8
#define PAMBL_FSK 5
#define PRERX_FSK 1
#define RXLEN_FSK (1+5+2)
#define BCN_INTV_osticks sec2osticks(BCN_INTV_sec)
#define TXRX_GUARD_osticks ms2osticks(TXRX_GUARD_ms)
#define JOIN_GUARD_osticks ms2osticks(JOIN_GUARD_ms)
#define DELAY_DNW1_osticks sec2osticks(DELAY_DNW1)
#define DELAY_DNW2_osticks sec2osticks(DELAY_DNW2)
#define DELAY_JACC1_osticks sec2osticks(DELAY_JACC1)
#define DELAY_JACC2_osticks sec2osticks(DELAY_JACC2)
#define DELAY_EXTDNW2_osticks sec2osticks(DELAY_EXTDNW2)
#define BCN_RESERVE_osticks ms2osticks(BCN_RESERVE_ms)
#define BCN_GUARD_osticks ms2osticks(BCN_GUARD_ms)
#define BCN_WINDOW_osticks ms2osticks(BCN_WINDOW_ms)
#define AIRTIME_BCN_osticks us2osticks(AIRTIME_BCN)
#if defined(CFG_eu868)
#define DNW2_SAFETY_ZONE ms2osticks(3000)
#endif
#if defined(CFG_us915)
#define DNW2_SAFETY_ZONE ms2osticks(750)
#endif
// Special APIs - for development or testing
#define isTESTMODE() 0
DEFINE_LMIC;
DECL_ON_LMIC_EVENT;
// Fwd decls.
static void engineUpdate(void);
static void startScan (void);
// ================================================================================
// BEG OS - default implementations for certain OS suport functions
#if !defined(HAS_os_calls)
#if !defined(os_rlsbf2)
u2_t os_rlsbf2 (xref2cu1_t buf) {
return (u2_t)(buf[0] | (buf[1]<<8));
}
#endif
#if !defined(os_rlsbf4)
u4_t os_rlsbf4 (xref2cu1_t buf) {
return (u4_t)(buf[0] | (buf[1]<<8) | ((u4_t)buf[2]<<16) | ((u4_t)buf[3]<<24));
}
#endif
#if !defined(os_rmsbf4)
u4_t os_rmsbf4 (xref2cu1_t buf) {
return (u4_t)(buf[3] | (buf[2]<<8) | ((u4_t)buf[1]<<16) | ((u4_t)buf[0]<<24));
}
#endif
#if !defined(os_wlsbf2)
void os_wlsbf2 (xref2u1_t buf, u2_t v) {
buf[0] = v;
buf[1] = v>>8;
}
#endif
#if !defined(os_wlsbf4)
void os_wlsbf4 (xref2u1_t buf, u4_t v) {
buf[0] = v;
buf[1] = v>>8;
buf[2] = v>>16;
buf[3] = v>>24;
}
#endif
#if !defined(os_wmsbf4)
void os_wmsbf4 (xref2u1_t buf, u4_t v) {
buf[3] = v;
buf[2] = v>>8;
buf[1] = v>>16;
buf[0] = v>>24;
}
#endif
#if !defined(os_getBattLevel)
u1_t os_getBattLevel (void) {
return MCMD_DEVS_BATT_NOINFO;
}
#endif
#if !defined(os_crc16)
// New CRC-16 CCITT(XMODEM) checksum for beacons:
u2_t os_crc16 (xref2u1_t data, uint len) {
u2_t remainder = 0;
u2_t polynomial = 0x1021;
for( uint i = 0; i < len; i++ ) {
remainder ^= data[i] << 8;
for( u1_t bit = 8; bit > 0; bit--) {
if( (remainder & 0x8000) )
remainder = (remainder << 1) ^ polynomial;
else
remainder <<= 1;
}
}
return remainder;
}
#endif
#endif // !HAS_os_calls
// END OS - default implementations for certain OS suport functions
// ================================================================================
// ================================================================================
// BEG AES
static void micB0 (u4_t devaddr, u4_t seqno, int dndir, int len) {
os_clearMem(AESaux,16);
AESaux[0] = 0x49;
AESaux[5] = dndir?1:0;
AESaux[15] = len;
os_wlsbf4(AESaux+ 6,devaddr);
os_wlsbf4(AESaux+10,seqno);
}
static int aes_verifyMic (xref2cu1_t key, u4_t devaddr, u4_t seqno, int dndir, xref2u1_t pdu, int len) {
micB0(devaddr, seqno, dndir, len);
os_copyMem(AESkey,key,16);
return os_aes(AES_MIC, pdu, len) == os_rmsbf4(pdu+len);
}
static void aes_appendMic (xref2cu1_t key, u4_t devaddr, u4_t seqno, int dndir, xref2u1_t pdu, int len) {
micB0(devaddr, seqno, dndir, len);
os_copyMem(AESkey,key,16);
// MSB because of internal structure of AES
os_wmsbf4(pdu+len, os_aes(AES_MIC, pdu, len));
}
static void aes_appendMic0 (xref2u1_t pdu, int len) {
os_getDevKey(AESkey);
os_wmsbf4(pdu+len, os_aes(AES_MIC|AES_MICNOAUX, pdu, len)); // MSB because of internal structure of AES
}
static int aes_verifyMic0 (xref2u1_t pdu, int len) {
os_getDevKey(AESkey);
return os_aes(AES_MIC|AES_MICNOAUX, pdu, len) == os_rmsbf4(pdu+len);
}
static void aes_encrypt (xref2u1_t pdu, int len) {
os_getDevKey(AESkey);
os_aes(AES_ENC, pdu, len);
}
static void aes_cipher (xref2cu1_t key, u4_t devaddr, u4_t seqno, int dndir, xref2u1_t payload, int len) {
if( len <= 0 )
return;
os_clearMem(AESaux, 16);
AESaux[0] = AESaux[15] = 1; // mode=cipher / dir=down / block counter=1
AESaux[5] = dndir?1:0;
os_wlsbf4(AESaux+ 6,devaddr);
os_wlsbf4(AESaux+10,seqno);
os_copyMem(AESkey,key,16);
os_aes(AES_CTR, payload, len);
}
static void aes_sessKeys (u2_t devnonce, xref2cu1_t artnonce, xref2u1_t nwkkey, xref2u1_t artkey) {
os_clearMem(nwkkey, 16);
nwkkey[0] = 0x01;
os_copyMem(nwkkey+1, artnonce, LEN_ARTNONCE+LEN_NETID);
os_wlsbf2(nwkkey+1+LEN_ARTNONCE+LEN_NETID, devnonce);
os_copyMem(artkey, nwkkey, 16);
artkey[0] = 0x02;
os_getDevKey(AESkey);
os_aes(AES_ENC, nwkkey, 16);
os_getDevKey(AESkey);
os_aes(AES_ENC, artkey, 16);
}
// END AES
// ================================================================================
// ================================================================================
// BEG LORA
#if defined(CFG_eu868) // ========================================
#define maxFrameLen(dr) ((dr)<=DR_SF9 ? maxFrameLens[(dr)] : 0xFF)
const u1_t maxFrameLens [] = { 64,64,64,123 };
const u1_t _DR2RPS_CRC[] = {
ILLEGAL_RPS,
(u1_t)MAKERPS(SF12, BW125, CR_4_5, 0, 0),
(u1_t)MAKERPS(SF11, BW125, CR_4_5, 0, 0),
(u1_t)MAKERPS(SF10, BW125, CR_4_5, 0, 0),
(u1_t)MAKERPS(SF9, BW125, CR_4_5, 0, 0),
(u1_t)MAKERPS(SF8, BW125, CR_4_5, 0, 0),
(u1_t)MAKERPS(SF7, BW125, CR_4_5, 0, 0),
(u1_t)MAKERPS(SF7, BW250, CR_4_5, 0, 0),
(u1_t)MAKERPS(FSK, BW125, CR_4_5, 0, 0),
ILLEGAL_RPS
};
static const s1_t TXPOWLEVELS[] = {
20, 14, 11, 8, 5, 2, 0,0, 0,0,0,0, 0,0,0,0
};
#define pow2dBm(mcmd_ladr_p1) (TXPOWLEVELS[(mcmd_ladr_p1&MCMD_LADR_POW_MASK)>>MCMD_LADR_POW_SHIFT])
#elif defined(CFG_us915) // ========================================
#define maxFrameLen(dr) ((dr)<=DR_SF11CR ? maxFrameLens[(dr)] : 0xFF)
const u1_t maxFrameLens [] = { 24,66,142,255,255,255,255,255, 66,142 };
const u1_t _DR2RPS_CRC[] = {
ILLEGAL_RPS,
MAKERPS(SF10, BW125, CR_4_5, 0, 0),
MAKERPS(SF9 , BW125, CR_4_5, 0, 0),
MAKERPS(SF8 , BW125, CR_4_5, 0, 0),
MAKERPS(SF7 , BW125, CR_4_5, 0, 0),
MAKERPS(SF8 , BW500, CR_4_5, 0, 0),
ILLEGAL_RPS ,
ILLEGAL_RPS ,
ILLEGAL_RPS ,
MAKERPS(SF12, BW500, CR_4_5, 0, 0),
MAKERPS(SF11, BW500, CR_4_5, 0, 0),
MAKERPS(SF10, BW500, CR_4_5, 0, 0),
MAKERPS(SF9 , BW500, CR_4_5, 0, 0),
MAKERPS(SF8 , BW500, CR_4_5, 0, 0),
MAKERPS(SF7 , BW500, CR_4_5, 0, 0),
ILLEGAL_RPS
};
#define pow2dBm(mcmd_ladr_p1) ((s1_t)(30 - (((mcmd_ladr_p1)&MCMD_LADR_POW_MASK)<<1)))
#endif // ================================================
static const u1_t SENSITIVITY[7][3] = {
// ------------bw----------
// 125kHz 250kHz 500kHz
{ 141-109, 141-109, 141-109 }, // FSK
{ 141-127, 141-124, 141-121 }, // SF7
{ 141-129, 141-126, 141-123 }, // SF8
{ 141-132, 141-129, 141-126 }, // SF9
{ 141-135, 141-132, 141-129 }, // SF10
{ 141-138, 141-135, 141-132 }, // SF11
{ 141-141, 141-138, 141-135 } // SF12
};
int getSensitivity (rps_t rps) {
return -141 + SENSITIVITY[getSf(rps)][getBw(rps)];
}
ostime_t calcAirTime (rps_t rps, u1_t plen) {
u1_t bw = getBw(rps); // 0,1,2 = 125,250,500kHz
u1_t sf = getSf(rps); // 0=FSK, 1..6 = SF7..12
if( sf == FSK ) {
return (plen+/*preamble*/5+/*syncword*/3+/*len*/1+/*crc*/2) * /*bits/byte*/8
* (s4_t)OSTICKS_PER_SEC / /*kbit/s*/50000;
}
u1_t sfx = 4*(sf+(7-SF7));
u1_t q = sfx - (sf >= SF11 ? 8 : 0);
int tmp = 8*plen - sfx + 28 + (getNocrc(rps)?0:16) - (getIh(rps)?20:0);
if( tmp > 0 ) {
tmp = (tmp + q - 1) / q;
tmp *= getCr(rps)+5;
tmp += 8;
} else {
tmp = 8;
}
tmp = (tmp<<2) + /*preamble*/49 /* 4 * (8 + 4.25) */;
// bw = 125000 = 15625 * 2^3
// 250000 = 15625 * 2^4
// 500000 = 15625 * 2^5
// sf = 7..12
//
// osticks = tmp * OSTICKS_PER_SEC * 1<<sf / bw
//
// 3 => counter reduced divisor 125000/8 => 15625
// 2 => counter 2 shift on tmp
sfx = sf+(7-SF7) - (3+2) - bw;
int div = 15625;
if( sfx > 4 ) {
// prevent 32bit signed int overflow in last step
div >>= sfx-4;
sfx = 4;
}
// Need 32bit arithmetic for this last step
return (((ostime_t)tmp << sfx) * OSTICKS_PER_SEC + div/2) / div;
}
extern inline s1_t rssi2s1 (int v);
extern inline int s12rssi (s1_t v);
extern inline float s12snr (s1_t v);
extern inline s1_t snr2s1 (double v);
extern inline rps_t updr2rps (dr_t dr);
extern inline rps_t dndr2rps (dr_t dr);
extern inline int isFasterDR (dr_t dr1, dr_t dr2);
extern inline int isSlowerDR (dr_t dr1, dr_t dr2);
extern inline dr_t incDR (dr_t dr);
extern inline dr_t decDR (dr_t dr);
extern inline dr_t assertDR (dr_t dr);
extern inline dr_t validDR (dr_t dr);
extern inline dr_t lowerDR (dr_t dr, u1_t n);
extern inline sf_t getSf (rps_t params);
extern inline rps_t setSf (rps_t params, sf_t sf);
extern inline bw_t getBw (rps_t params);
extern inline rps_t setBw (rps_t params, bw_t cr);
extern inline cr_t getCr (rps_t params);
extern inline rps_t setCr (rps_t params, cr_t cr);
extern inline int getNocrc (rps_t params);
extern inline rps_t setNocrc (rps_t params, int nocrc);
extern inline int getIh (rps_t params);
extern inline rps_t setIh (rps_t params, int ih);
extern inline rps_t makeRps (sf_t sf, bw_t bw, cr_t cr, int ih, int nocrc);
extern inline int sameSfBw (rps_t r1, rps_t r2);
// END LORA
// ================================================================================
// Adjust DR for TX retries
// - indexed by retry count
// - return steps to lower DR
static const u1_t DRADJUST[2+TXCONF_ATTEMPTS] = {
// normal frames - 1st try / no retry
0,
// confirmed frames
0,0,1,0,1,0,1,0,0
};
// Table below defines the size of one symbol as
// symtime = 256us * 2^T(sf,bw)
// 256us is called one symunit.
// SF:
// BW: |__7___8___9__10__11__12
// 125kHz | 2 3 4 5 6 7
// 250kHz | 1 2 3 4 5 6
// 500kHz | 0 1 2 3 4 5
//
// Times for half symbol per DR
// Per DR table to minimize rounding errors
static const ostime_t DR2HSYM_osticks[] = {
#if defined(CFG_eu868)
#define dr2hsym(dr) (DR2HSYM_osticks[(dr)])
us2osticksRound(128<<7), // DR_SF12
us2osticksRound(128<<6), // DR_SF11
us2osticksRound(128<<5), // DR_SF10
us2osticksRound(128<<4), // DR_SF9
us2osticksRound(128<<3), // DR_SF8
us2osticksRound(128<<2), // DR_SF7
us2osticksRound(128<<1), // DR_SF7B
us2osticksRound(80) // FSK -- not used (time for 1/2 byte)
#elif defined(CFG_us915)
#define dr2hsym(dr) (DR2HSYM_osticks[(dr)&7]) // map DR_SFnCR -> 0-6
us2osticksRound(128<<5), // DR_SF10 DR_SF12CR
us2osticksRound(128<<4), // DR_SF9 DR_SF11CR
us2osticksRound(128<<3), // DR_SF8 DR_SF10CR
us2osticksRound(128<<2), // DR_SF7 DR_SF9CR
us2osticksRound(128<<1), // DR_SF8C DR_SF8CR
us2osticksRound(128<<0) // ------ DR_SF7CR
#endif
};
static ostime_t calcRxWindow (u1_t secs, dr_t dr) {
ostime_t rxoff, err;
if( secs==0 ) {
// aka 128 secs (next becaon)
rxoff = LMIC.drift;
err = LMIC.lastDriftDiff;
} else {
// scheduled RX window within secs into current beacon period
rxoff = (LMIC.drift * (ostime_t)secs) >> BCN_INTV_exp;
err = (LMIC.lastDriftDiff * (ostime_t)secs) >> BCN_INTV_exp;
}
u1_t rxsyms = MINRX_SYMS;
err += (ostime_t)LMIC.maxDriftDiff * LMIC.missedBcns;
LMIC.rxsyms = MINRX_SYMS + (err / dr2hsym(dr));
return (rxsyms-PAMBL_SYMS) * dr2hsym(dr) + rxoff;
}
// Setup beacon RX parameters assuming we have an error of ms (aka +/-(ms/2))
static void calcBcnRxWindowFromMillis (u1_t ms, bit_t ini) {
if( ini ) {
LMIC.drift = 0;
LMIC.maxDriftDiff = 0;
LMIC.missedBcns = 0;
LMIC.bcninfo.flags |= BCN_NODRIFT|BCN_NODDIFF;
}
ostime_t hsym = dr2hsym(DR_BCN);
LMIC.bcnRxsyms = MINRX_SYMS + ms2osticksCeil(ms) / hsym;
LMIC.bcnRxtime = LMIC.bcninfo.txtime + BCN_INTV_osticks - (LMIC.bcnRxsyms-PAMBL_SYMS) * hsym;
}
// Setup scheduled RX window (ping/multicast slot)
static void rxschedInit (xref2rxsched_t rxsched) {
os_clearMem(AESkey,16);
os_clearMem(LMIC.frame+8,8);
os_wlsbf4(LMIC.frame, LMIC.bcninfo.time);
os_wlsbf4(LMIC.frame+4, LMIC.devaddr);
os_aes(AES_ENC,LMIC.frame,16);
u1_t intvExp = rxsched->intvExp;
ostime_t off = os_rlsbf2(LMIC.frame) & (0x0FFF >> (7 - intvExp)); // random offset (slot units)
rxsched->rxbase = (LMIC.bcninfo.txtime +
BCN_RESERVE_osticks +
ms2osticks(BCN_SLOT_SPAN_ms * off)); // random offset osticks
rxsched->slot = 0;
rxsched->rxtime = rxsched->rxbase - calcRxWindow(/*secs BCN_RESERVE*/2+(1<<intvExp),rxsched->dr);
rxsched->rxsyms = LMIC.rxsyms;
}
static bit_t rxschedNext (xref2rxsched_t rxsched, ostime_t cando) {
again:
if( rxsched->rxtime - cando >= 0 )
return 1;
u1_t slot;
if( (slot=rxsched->slot) >= 128 )
return 0;
u1_t intv = 1<<rxsched->intvExp;
if( (rxsched->slot = (slot += (intv))) >= 128 )
return 0;
rxsched->rxtime = rxsched->rxbase
+ ((BCN_WINDOW_osticks * (ostime_t)slot) >> BCN_INTV_exp)
- calcRxWindow(/*secs BCN_RESERVE*/2+slot+intv,rxsched->dr);
rxsched->rxsyms = LMIC.rxsyms;
goto again;
}
static ostime_t rndDelay (u1_t secSpan) {
u2_t r = os_getRndU2();
ostime_t delay = r;
if( delay > OSTICKS_PER_SEC )
delay = r % (u2_t)OSTICKS_PER_SEC;
if( secSpan > 0 )
delay += ((u1_t)r % secSpan) * OSTICKS_PER_SEC;
return delay;
}
static void txDelay (ostime_t reftime, u1_t secSpan) {
reftime += rndDelay(secSpan);
if( LMIC.globalDutyRate == 0 || (reftime - LMIC.globalDutyAvail) > 0 ) {
LMIC.globalDutyAvail = reftime;
LMIC.opmode |= OP_RNDTX;
}
}
static void setDrJoin (u1_t reason, u1_t dr) {
EV(drChange, INFO, (e_.reason = reason,
e_.deveui = MAIN::CDEV->getEui(),
e_.dr = dr|DR_PAGE,
e_.txpow = LMIC.adrTxPow,
e_.prevdr = LMIC.datarate|DR_PAGE,
e_.prevtxpow = LMIC.adrTxPow));
LMIC.datarate = dr;
DO_DEVDB(LMIC.datarate,datarate);
}
static void setDrTxpow (u1_t reason, u1_t dr, s1_t pow) {
EV(drChange, INFO, (e_.reason = reason,
e_.deveui = MAIN::CDEV->getEui(),
e_.dr = dr|DR_PAGE,
e_.txpow = pow,
e_.prevdr = LMIC.datarate|DR_PAGE,
e_.prevtxpow = LMIC.adrTxPow));
if( pow != KEEP_TXPOW )
LMIC.adrTxPow = pow;
if( LMIC.datarate != dr ) {
LMIC.datarate = dr;
DO_DEVDB(LMIC.datarate,datarate);
LMIC.opmode |= OP_NEXTCHNL;
}
}
void LMIC_stopPingable (void) {
LMIC.opmode &= ~(OP_PINGABLE|OP_PINGINI);
}
void LMIC_setPingable (u1_t intvExp) {
// Change setting
LMIC.ping.intvExp = (intvExp & 0x7);
LMIC.opmode |= OP_PINGABLE;
// App may call LMIC_enableTracking() explicitely before
// Otherwise tracking is implicitly enabled here
if( (LMIC.opmode & (OP_TRACK|OP_SCAN)) == 0 && LMIC.bcninfoTries == 0 )
LMIC_enableTracking(0);
}
#if defined(CFG_eu868)
// ================================================================================
//
// BEG: EU868 related stuff
//
enum { NUM_DEFAULT_CHANNELS=6 };
static const u4_t iniChannelFreq[12] = {
// Join frequencies and duty cycle limit (0.1%)
EU868_F1|BAND_MILLI, EU868_J4|BAND_MILLI,
EU868_F2|BAND_MILLI, EU868_J5|BAND_MILLI,
EU868_F3|BAND_MILLI, EU868_J6|BAND_MILLI,
// Default operational frequencies
EU868_F1|BAND_CENTI, EU868_F2|BAND_CENTI, EU868_F3|BAND_CENTI,
EU868_F4|BAND_MILLI, EU868_F5|BAND_MILLI, EU868_F6|BAND_DECI
};
static void initDefaultChannels (bit_t join) {
os_clearMem(&LMIC.channelFreq, sizeof(LMIC.channelFreq));
os_clearMem(&LMIC.channelDrMap, sizeof(LMIC.channelDrMap));
os_clearMem(&LMIC.bands, sizeof(LMIC.bands));
LMIC.channelMap = 0x1F;
u1_t su = join ? 0 : 6;
for( u1_t fu=0; fu<6; fu++,su++ ) {
LMIC.channelFreq[fu] = iniChannelFreq[su];
LMIC.channelDrMap[fu] = DR_RANGE_MAP(DR_SF12,DR_SF7);
}
if( !join ) {
LMIC.channelDrMap[5] = DR_RANGE_MAP(DR_SF12,DR_SF7);
LMIC.channelDrMap[1] = DR_RANGE_MAP(DR_SF12,DR_FSK);
}
LMIC.bands[BAND_MILLI].txcap = 1000; // 0.1%
LMIC.bands[BAND_MILLI].txpow = 14;
LMIC.bands[BAND_MILLI].lastchnl = os_getRndU1() % MAX_CHANNELS;
LMIC.bands[BAND_CENTI].txcap = 100; // 1%
LMIC.bands[BAND_CENTI].txpow = 14;
LMIC.bands[BAND_CENTI].lastchnl = os_getRndU1() % MAX_CHANNELS;
LMIC.bands[BAND_DECI ].txcap = 10; // 10%
LMIC.bands[BAND_DECI ].txpow = 27;
LMIC.bands[BAND_CENTI].lastchnl = os_getRndU1() % MAX_CHANNELS;
LMIC.bands[BAND_MILLI].avail =
LMIC.bands[BAND_CENTI].avail =
LMIC.bands[BAND_DECI ].avail = os_getTime();
}
bit_t LMIC_setupBand (u1_t bandidx, s1_t txpow, u2_t txcap) {
if( bandidx > BAND_AUX ) return 0;
band_t* b = &LMIC.bands[bandidx];
b->txpow = txpow;
b->txcap = txcap;
b->avail = os_getTime();
b->lastchnl = os_getRndU1() % MAX_CHANNELS;
return 1;
}
bit_t LMIC_setupChannel (u1_t chidx, u4_t freq, u2_t drmap, s1_t band) {
if( chidx >= MAX_CHANNELS )
return 0;
if( band == -1 ) {
if( freq >= 869400000 && freq <= 869650000 )
freq |= BAND_DECI; // 10% 27dBm
else if( (freq >= 868000000 && freq <= 868600000) ||
(freq >= 869700000 && freq <= 870000000) )
freq |= BAND_CENTI; // 1% 14dBm
else
freq |= BAND_MILLI; // 0.1% 14dBm
} else {
if( band > BAND_AUX ) return 0;
freq = (freq&~3) | band;
}
LMIC.channelFreq [chidx] = freq;
LMIC.channelDrMap[chidx] = drmap==0 ? DR_RANGE_MAP(DR_SF12,DR_SF7) : drmap;
LMIC.channelMap |= 1<<chidx; // enabled right away
return 1;
}
void LMIC_disableChannel (u1_t channel) {
LMIC.channelFreq[channel] = 0;
LMIC.channelDrMap[channel] = 0;
LMIC.channelMap &= ~(1<<channel);
}
static u4_t convFreq (xref2u1_t ptr) {
u4_t freq = (os_rlsbf4(ptr-1) >> 8) * 100;
if( freq < EU868_FREQ_MIN || freq > EU868_FREQ_MAX )
freq = 0;
return freq;
}
static u1_t mapChannels (u1_t chpage, u2_t chmap) {
// Bad page, disable all channel, enable non-existent
if( chpage != 0 || chmap==0 || (chmap & ~LMIC.channelMap) != 0 )
return 0; // illegal input
for( u1_t chnl=0; chnl<MAX_CHANNELS; chnl++ ) {
if( (chmap & (1<<chnl)) != 0 && LMIC.channelFreq[chnl] == 0 )
chmap &= ~(1<<chnl); // ignore - channel is not defined
}
LMIC.channelMap = chmap;
return 1;
}
static void updateTx (ostime_t txbeg) {
u4_t freq = LMIC.channelFreq[LMIC.txChnl];
// Update global/band specific duty cycle stats
ostime_t airtime = calcAirTime(LMIC.rps, LMIC.dataLen);
// Update channel/global duty cycle stats
xref2band_t band = &LMIC.bands[freq & 0x3];
LMIC.freq = freq & ~(u4_t)3;
LMIC.txpow = band->txpow;
band->avail = txbeg + airtime * band->txcap;
if( LMIC.globalDutyRate != 0 )
LMIC.globalDutyAvail = txbeg + (airtime<<LMIC.globalDutyRate);
}
static ostime_t nextTx (ostime_t now) {
u1_t bmap=0xF;
do {
ostime_t mintime = now + /*10h*/36000*OSTICKS_PER_SEC;
u1_t band=0;
for( u1_t bi=0; bi<4; bi++ ) {
if( (bmap & (1<<bi)) && mintime - LMIC.bands[bi].avail > 0 )
mintime = LMIC.bands[band = bi].avail;
}
// Find next channel in given band
u1_t chnl = LMIC.bands[band].lastchnl;
for( u1_t ci=0; ci<MAX_CHANNELS; ci++ ) {
if( (chnl = (chnl+1)) >= MAX_CHANNELS )
chnl -= MAX_CHANNELS;
if( (LMIC.channelMap & (1<<chnl)) != 0 && // channel enabled
(LMIC.channelDrMap[chnl] & (1<<(LMIC.datarate&0xF))) != 0 &&
band == (LMIC.channelFreq[chnl] & 0x3) ) { // in selected band
LMIC.txChnl = LMIC.bands[band].lastchnl = chnl;
return mintime;
}
}
if( (bmap &= ~(1<<band)) == 0 ) {
// No feasible channel found!
return mintime;
}
} while(1);
}
static void setBcnRxParams (void) {
LMIC.dataLen = 0;
LMIC.freq = LMIC.channelFreq[LMIC.bcnChnl] & ~(u4_t)3;
LMIC.rps = setIh(setNocrc(dndr2rps((dr_t)DR_BCN),1),LEN_BCN);
}
#define setRx1Params() /*LMIC.freq/rps remain unchanged*/
static void initJoinLoop (void) {
LMIC.txChnl = os_getRndU1() % 6;
LMIC.adrTxPow = 14;
setDrJoin(DRCHG_SET, DR_SF7);
initDefaultChannels(1);
ASSERT((LMIC.opmode & OP_NEXTCHNL)==0);
LMIC.txend = LMIC.bands[BAND_MILLI].avail + rndDelay(8);
}
static ostime_t nextJoinState (void) {
u1_t failed = 0;
// Try 869.x and then 864.x with same DR
// If both fail try next lower datarate
if( ++LMIC.txChnl == 6 )
LMIC.txChnl = 0;
if( (++LMIC.txCnt & 1) == 0 ) {
// Lower DR every 2nd try (having tried 868.x and 864.x with the same DR)
if( LMIC.datarate == DR_SF12 )
failed = 1; // we have tried all DR - signal EV_JOIN_FAILED
else
setDrJoin(DRCHG_NOJACC, decDR((dr_t)LMIC.datarate));
}
// Clear NEXTCHNL because join state engine controls channel hopping
LMIC.opmode &= ~OP_NEXTCHNL;
// Move txend to randomize synchronized concurrent joins.
// Duty cycle is based on txend.
ostime_t time = os_getTime();
if( time - LMIC.bands[BAND_MILLI].avail < 0 )
time = LMIC.bands[BAND_MILLI].avail;
LMIC.txend = time +
(isTESTMODE()
// Avoid collision with JOIN ACCEPT @ SF12 being sent by GW (but we missed it)
? DNW2_SAFETY_ZONE
// Otherwise: randomize join (street lamp case):
// SF12:255, SF11:127, .., SF7:8secs
: DNW2_SAFETY_ZONE+rndDelay(255>>LMIC.datarate));
// 1 - triggers EV_JOIN_FAILED event
return failed;
}
//
// END: EU868 related stuff
//
// ================================================================================
#elif defined(CFG_us915)
// ================================================================================
//
// BEG: US915 related stuff
//
static void initDefaultChannels (void) {
for( u1_t i=0; i<4; i++ )
LMIC.channelMap[i] = 0xFFFF;
LMIC.channelMap[4] = 0x00FF;
}
static u4_t convFreq (xref2u1_t ptr) {
u4_t freq = (os_rlsbf4(ptr-1) >> 8) * 100;
if( freq < US915_FREQ_MIN || freq > US915_FREQ_MAX )
freq = 0;
return freq;
}
bit_t LMIC_setupChannel (u1_t chidx, u4_t freq, u2_t drmap, s1_t band) {
if( chidx < 72 || chidx >= 72+MAX_XCHANNELS )
return 0; // channels 0..71 are hardwired
chidx -= 72;
LMIC.xchFreq[chidx] = freq;
LMIC.xchDrMap[chidx] = drmap==0 ? DR_RANGE_MAP(DR_SF10,DR_SF8C) : drmap;
LMIC.channelMap[chidx>>4] |= (1<<(chidx&0xF));
return 1;
}
void LMIC_disableChannel (u1_t channel) {
if( channel < 72+MAX_XCHANNELS )
LMIC.channelMap[channel/4] &= ~(1<<(channel&0xF));
}
static u1_t mapChannels (u1_t chpage, u2_t chmap) {
if( chpage == MCMD_LADR_CHP_125ON || chpage == MCMD_LADR_CHP_125OFF ) {
u2_t en125 = chpage == MCMD_LADR_CHP_125ON ? 0xFFFF : 0x0000;
for( u1_t u=0; u<4; u++ )
LMIC.channelMap[u] = en125;
LMIC.channelMap[64/16] = chmap;
} else {
if( chpage >= (72+MAX_XCHANNELS+15)/16 )
return 0;
LMIC.channelMap[chpage] = chmap;
}
return 1;
}
static void updateTx (ostime_t txbeg) {
u1_t chnl = LMIC.txChnl;
if( chnl < 64 ) {
LMIC.freq = US915_125kHz_UPFBASE + chnl*US915_125kHz_UPFSTEP;
LMIC.txpow = 30;
return;
}
LMIC.txpow = 26;
if( chnl < 64+8 ) {
LMIC.freq = US915_500kHz_UPFBASE + (chnl-64)*US915_500kHz_UPFSTEP;
} else {
ASSERT(chnl < 64+8+MAX_XCHANNELS);
LMIC.freq = LMIC.xchFreq[chnl-72];
}
// Update global duty cycle stats
if( LMIC.globalDutyRate != 0 ) {
ostime_t airtime = calcAirTime(LMIC.rps, LMIC.dataLen);
LMIC.globalDutyAvail = txbeg + (airtime<<LMIC.globalDutyRate);
}
}
// US does not have duty cycling - return now as earliest TX time
#define nextTx(now) (_nextTx(),(now))
static void _nextTx (void) {
if( LMIC.chRnd==0 )
LMIC.chRnd = os_getRndU1() & 0x3F;
if( LMIC.datarate >= DR_SF8C ) { // 500kHz
u1_t map = LMIC.channelMap[64/16]&0xFF;
for( u1_t i=0; i<8; i++ ) {
if( (map & (1<<(++LMIC.chRnd & 7))) != 0 ) {
LMIC.txChnl = 64 + (LMIC.chRnd & 7);
return;
}
}
} else { // 125kHz
for( u1_t i=0; i<64; i++ ) {
u1_t chnl = ++LMIC.chRnd & 0x3F;
if( (LMIC.channelMap[(chnl >> 4)] & (1<<(chnl & 0xF))) != 0 ) {
LMIC.txChnl = chnl;
return;
}
}
}
// No feasible channel found! Keep old one.
}
static void setBcnRxParams (void) {
LMIC.dataLen = 0;
LMIC.freq = US915_500kHz_DNFBASE + LMIC.bcnChnl * US915_500kHz_DNFSTEP;
LMIC.rps = setIh(setNocrc(dndr2rps((dr_t)DR_BCN),1),LEN_BCN);
}
#define setRx1Params() { \
LMIC.freq = US915_500kHz_DNFBASE + (LMIC.txChnl & 0x7) * US915_500kHz_DNFSTEP; \
if( /* TX datarate */LMIC.dndr < DR_SF8C ) \
LMIC.dndr += DR_SF10CR - DR_SF10; \
else if( LMIC.dndr == DR_SF8C ) \
LMIC.dndr = DR_SF7CR; \
LMIC.rps = dndr2rps(LMIC.dndr); \
}
static void initJoinLoop (void) {
LMIC.chRnd = 0;
LMIC.txChnl = 0;
LMIC.adrTxPow = 20;
ASSERT((LMIC.opmode & OP_NEXTCHNL)==0);
LMIC.txend = os_getTime();
setDrJoin(DRCHG_SET, DR_SF7);
}
static ostime_t nextJoinState (void) {
// Try the following:
// SF7/8/9/10 on a random channel 0..63
// SF8C on a random channel 64..71
//
u1_t failed = 0;
if( LMIC.datarate != DR_SF8C ) {
LMIC.txChnl = 64+(LMIC.txChnl&7);
setDrJoin(DRCHG_SET, DR_SF8C);
} else {
LMIC.txChnl = os_getRndU1() & 0x3F;
s1_t dr = DR_SF7 - ++LMIC.txCnt;
if( dr < DR_SF10 ) {
dr = DR_SF10;
failed = 1; // All DR exhausted - signal failed
}
setDrJoin(DRCHG_SET, dr);
}
LMIC.opmode &= ~OP_NEXTCHNL;
LMIC.txend = os_getTime() +
(isTESTMODE()
// Avoid collision with JOIN ACCEPT being sent by GW (but we missed it - GW is still busy)
? DNW2_SAFETY_ZONE
// Otherwise: randomize join (street lamp case):
// SF10:16, SF9=8,..SF8C:1secs
: rndDelay(16>>LMIC.datarate));
// 1 - triggers EV_JOIN_FAILED event
return failed;
}
//
// END: US915 related stuff
//
// ================================================================================
#else
#error Unsupported frequency band!
#endif
static void runEngineUpdate (xref2osjob_t osjob) {
engineUpdate();
}
static void reportEvent (ev_t ev) {
EV(devCond, INFO, (e_.reason = EV::devCond_t::LMIC_EV,
e_.eui = MAIN::CDEV->getEui(),
e_.info = ev));
ON_LMIC_EVENT(ev);
engineUpdate();
}
static void runReset (xref2osjob_t osjob) {
// Disable session
LMIC_reset();
LMIC_startJoining();
reportEvent(EV_RESET);
}
static void stateJustJoined (void) {
LMIC.seqnoDn = LMIC.seqnoUp = 0;
LMIC.rejoinCnt = 0;
LMIC.dnConf = LMIC.adrChanged = LMIC.ladrAns = LMIC.devsAns = 0;
LMIC.moreData = LMIC.dn2Ans = LMIC.snchAns = LMIC.dutyCapAns = 0;
LMIC.pingSetAns = 0;
LMIC.upRepeat = 0;
LMIC.adrAckReq = LINK_CHECK_INIT;
LMIC.dn2Dr = DR_DNW2;
LMIC.dn2Freq = FREQ_DNW2;
LMIC.bcnChnl = CHNL_BCN;
LMIC.ping.freq = FREQ_PING;
LMIC.ping.dr = DR_PING;
}
// ================================================================================
// Decoding frames
// Decode beacon - do not overwrite bcninfo unless we have a match!
static int decodeBeacon (void) {
ASSERT(LMIC.dataLen == LEN_BCN); // implicit header RX guarantees this
xref2u1_t d = LMIC.frame;
if(
#if CFG_eu868
d[OFF_BCN_CRC1] != (u1_t)os_crc16(d,OFF_BCN_CRC1)
#elif CFG_us915
os_rlsbf2(&d[OFF_BCN_CRC1]) != os_crc16(d,OFF_BCN_CRC1)
#endif
)
return 0; // first (common) part fails CRC check
// First set of fields is ok
u4_t bcnnetid = os_rlsbf4(&d[OFF_BCN_NETID]) & 0xFFFFFF;
if( bcnnetid != LMIC.netid )
return -1; // not the beacon we're looking for
LMIC.bcninfo.flags &= ~(BCN_PARTIAL|BCN_FULL);
// Match - update bcninfo structure
LMIC.bcninfo.snr = LMIC.snr;
LMIC.bcninfo.rssi = LMIC.rssi;
LMIC.bcninfo.txtime = LMIC.rxtime - AIRTIME_BCN_osticks;
LMIC.bcninfo.time = os_rlsbf4(&d[OFF_BCN_TIME]);
LMIC.bcninfo.flags |= BCN_PARTIAL;
// Check 2nd set
if( os_rlsbf2(&d[OFF_BCN_CRC2]) != os_crc16(d,OFF_BCN_CRC2) )
return 1;
// Second set of fields is ok
LMIC.bcninfo.lat = (s4_t)os_rlsbf4(&d[OFF_BCN_LAT-1]) >> 8; // read as signed 24-bit
LMIC.bcninfo.lon = (s4_t)os_rlsbf4(&d[OFF_BCN_LON-1]) >> 8; // ditto
LMIC.bcninfo.info = d[OFF_BCN_INFO];
LMIC.bcninfo.flags |= BCN_FULL;
return 2;
}
static bit_t decodeFrame (void) {
xref2u1_t d = LMIC.frame;
u1_t hdr = d[0];
u1_t ftype = hdr & HDR_FTYPE;
int dlen = LMIC.dataLen;
if( dlen < OFF_DAT_OPTS+4 ||
(hdr & HDR_MAJOR) != HDR_MAJOR_V1 ||
(ftype != HDR_FTYPE_DADN && ftype != HDR_FTYPE_DCDN) ) {
// Basic sanity checks failed
EV(specCond, WARN, (e_.reason = EV::specCond_t::UNEXPECTED_FRAME,
e_.eui = MAIN::CDEV->getEui(),
e_.info = dlen < 4 ? 0 : os_rlsbf4(&d[dlen-4]),
e_.info2 = hdr + (dlen<<8)));
norx:
LMIC.dataLen = 0;
return 0;
}
// Validate exact frame length
// Note: device address was already read+evaluated in order to arrive here.
int fct = d[OFF_DAT_FCT];
u4_t addr = os_rlsbf4(&d[OFF_DAT_ADDR]);
u4_t seqno = os_rlsbf2(&d[OFF_DAT_SEQNO]);
int olen = fct & FCT_OPTLEN;
int ackup = (fct & FCT_ACK) != 0 ? 1 : 0; // ACK last up frame
int poff = OFF_DAT_OPTS+olen;
int pend = dlen-4; // MIC
if( addr != LMIC.devaddr ) {
EV(specCond, WARN, (e_.reason = EV::specCond_t::ALIEN_ADDRESS,
e_.eui = MAIN::CDEV->getEui(),
e_.info = addr,
e_.info2 = LMIC.devaddr));
goto norx;
}
if( poff > pend ) {
EV(specCond, ERR, (e_.reason = EV::specCond_t::CORRUPTED_FRAME,
e_.eui = MAIN::CDEV->getEui(),
e_.info = 0x1000000 + (poff-pend) + (fct<<8) + (dlen<<16)));
goto norx;
}
int port = -1;
int replayConf = 0;
if( pend > poff )
port = d[poff++];
seqno = LMIC.seqnoDn + (u2_t)(seqno - LMIC.seqnoDn);
if( !aes_verifyMic(LMIC.nwkKey, LMIC.devaddr, seqno, /*dn*/1, d, pend) ) {
EV(spe3Cond, ERR, (e_.reason = EV::spe3Cond_t::CORRUPTED_MIC,
e_.eui1 = MAIN::CDEV->getEui(),
e_.info1 = Base::lsbf4(&d[pend]),
e_.info2 = seqno,
e_.info3 = LMIC.devaddr));
goto norx;
}
if( seqno < LMIC.seqnoDn ) {
if( (s4_t)seqno > (s4_t)LMIC.seqnoDn ) {
EV(specCond, INFO, (e_.reason = EV::specCond_t::DNSEQNO_ROLL_OVER,
e_.eui = MAIN::CDEV->getEui(),
e_.info = LMIC.seqnoDn,
e_.info2 = seqno));
goto norx;
}
if( seqno != LMIC.seqnoDn-1 || !LMIC.dnConf || ftype != HDR_FTYPE_DCDN ) {
EV(specCond, INFO, (e_.reason = EV::specCond_t::DNSEQNO_OBSOLETE,
e_.eui = MAIN::CDEV->getEui(),
e_.info = LMIC.seqnoDn,
e_.info2 = seqno));
goto norx;
}
// Replay of previous sequence number allowed only if
// previous frame and repeated both requested confirmation
replayConf = 1;
}
else {
if( seqno > LMIC.seqnoDn ) {
EV(specCond, INFO, (e_.reason = EV::specCond_t::DNSEQNO_SKIP,
e_.eui = MAIN::CDEV->getEui(),
e_.info = LMIC.seqnoDn,
e_.info2 = seqno));
}
LMIC.seqnoDn = seqno+1; // next number to be expected
DO_DEVDB(LMIC.seqnoDn,seqnoDn);
// DN frame requested confirmation - provide ACK once with next UP frame
LMIC.dnConf = (ftype == HDR_FTYPE_DCDN ? FCT_ACK : 0);
}
if( LMIC.dnConf || (fct & FCT_MORE) )
LMIC.opmode |= OP_POLL;
// We heard from network
LMIC.adrChanged = LMIC.rejoinCnt = 0;
if( LMIC.adrAckReq != LINK_CHECK_OFF )
LMIC.adrAckReq = LINK_CHECK_INIT;
// Process OPTS
int m = LMIC.rssi - RSSI_OFF - getSensitivity(LMIC.rps);
LMIC.margin = m < 0 ? 0 : m > 254 ? 254 : m;
xref2u1_t opts = &d[OFF_DAT_OPTS];
int oidx = 0;
while( oidx < olen ) {
switch( opts[oidx] ) {
case MCMD_LCHK_ANS: {
//int gwmargin = opts[oidx+1];
//int ngws = opts[oidx+2];
oidx += 3;
continue;
}
case MCMD_LADR_REQ: {
u1_t p1 = opts[oidx+1]; // txpow + DR
u2_t chmap = os_rlsbf2(&opts[oidx+2]);// list of enabled channels
u1_t chpage = opts[oidx+4] & MCMD_LADR_CHPAGE_MASK; // channel page
u1_t uprpt = opts[oidx+4] & MCMD_LADR_REPEAT_MASK; // up repeat count
oidx += 5;
LMIC.ladrAns = 0x80 | // Include an answer into next frame up
MCMD_LADR_ANS_POWACK | MCMD_LADR_ANS_CHACK | MCMD_LADR_ANS_DRACK;
if( !mapChannels(chpage, chmap) )
LMIC.ladrAns &= ~MCMD_LADR_ANS_CHACK;
dr_t dr = (dr_t)(p1>>MCMD_LADR_DR_SHIFT);
if( !validDR(dr) ) {
LMIC.ladrAns &= ~MCMD_LADR_ANS_DRACK;
EV(specCond, ERR, (e_.reason = EV::specCond_t::BAD_MAC_CMD,
e_.eui = MAIN::CDEV->getEui(),
e_.info = Base::lsbf4(&d[pend]),
e_.info2 = Base::msbf4(&opts[oidx-4])));
}
if( (LMIC.ladrAns & 0x7F) == (MCMD_LADR_ANS_POWACK | MCMD_LADR_ANS_CHACK | MCMD_LADR_ANS_DRACK) ) {
// Nothing went wrong - use settings
LMIC.upRepeat = uprpt;
setDrTxpow(DRCHG_NWKCMD, dr, pow2dBm(p1));
}
LMIC.adrChanged = 1; // Trigger an ACK to NWK
continue;
}
case MCMD_DEVS_REQ: {
LMIC.devsAns = 1;
oidx += 1;
continue;
}
case MCMD_DN2P_SET: {
dr_t dr = (dr_t)(opts[oidx+1] & 0x0F);
u4_t freq = convFreq(&opts[oidx+2]);
oidx += 5;
LMIC.dn2Ans = 0x80; // answer pending
if( validDR(dr) )
LMIC.dn2Ans |= MCMD_DN2P_ANS_DRACK;
if( freq != 0 )
LMIC.dn2Ans |= MCMD_DN2P_ANS_CHACK;
if( LMIC.dn2Ans == (0x80|MCMD_DN2P_ANS_DRACK|MCMD_DN2P_ANS_CHACK) ) {
LMIC.dn2Dr = dr;
LMIC.dn2Freq = freq;
DO_DEVDB(LMIC.dn2Dr,dn2Dr);
DO_DEVDB(LMIC.dn2Freq,dn2Freq);
}
continue;
}
case MCMD_DCAP_REQ: {
u1_t cap = opts[oidx+1];
oidx += 2;
// A value cap=0xFF means device is OFF unless enabled again manually.
if( cap==0xFF )
LMIC.opmode |= OP_SHUTDOWN; // stop any sending
LMIC.globalDutyRate = cap & 0xF;
LMIC.globalDutyAvail = os_getTime();
DO_DEVDB(cap,dutyCap);
LMIC.dutyCapAns = 1;
continue;
}
case MCMD_SNCH_REQ: {
u1_t chidx = opts[oidx+1]; // channel
u4_t freq = convFreq(&opts[oidx+2]); // freq
u1_t drs = opts[oidx+5]; // datarate span
LMIC.snchAns = 0x80;
if( freq != 0 && LMIC_setupChannel(chidx, freq, DR_RANGE_MAP(drs&0xF,drs>>4), -1) )
LMIC.snchAns |= MCMD_SNCH_ANS_DRACK|MCMD_SNCH_ANS_FQACK;
oidx += 6;
continue;
}
case MCMD_PING_SET: {
u4_t freq = convFreq(&opts[oidx+1]);
oidx += 4;
u1_t flags = 0x80;
if( freq != 0 ) {
flags |= MCMD_PING_ANS_FQACK;
LMIC.ping.freq = freq;
DO_DEVDB(LMIC.ping.intvExp, pingIntvExp);
DO_DEVDB(LMIC.ping.freq, pingFreq);
DO_DEVDB(LMIC.ping.dr, pingDr);
}
LMIC.pingSetAns = flags;
continue;
}
case MCMD_BCNI_ANS: {
// Ignore if tracking already enabled
if( (LMIC.opmode & OP_TRACK) == 0 ) {
LMIC.bcnChnl = opts[oidx+3];
// Enable tracking - bcninfoTries
LMIC.opmode |= OP_TRACK;
// Cleared later in txComplete handling - triggers EV_BEACON_FOUND
ASSERT(LMIC.bcninfoTries!=0);
// Setup RX parameters
LMIC.bcninfo.txtime = (LMIC.rxtime
+ ms2osticks(os_rlsbf2(&opts[oidx+1]) * MCMD_BCNI_TUNIT)
+ ms2osticksCeil(MCMD_BCNI_TUNIT/2)
- BCN_INTV_osticks);
LMIC.bcninfo.flags = 0; // txtime above cannot be used as reference (BCN_PARTIAL|BCN_FULL cleared)
calcBcnRxWindowFromMillis(MCMD_BCNI_TUNIT,1); // error of +/-N ms
EV(lostFrame, INFO, (e_.reason = EV::lostFrame_t::MCMD_BCNI_ANS,
e_.eui = MAIN::CDEV->getEui(),
e_.lostmic = Base::lsbf4(&d[pend]),
e_.info = (LMIC.missedBcns |
(osticks2us(LMIC.bcninfo.txtime + BCN_INTV_osticks
- LMIC.bcnRxtime) << 8)),
e_.time = MAIN::CDEV->ostime2ustime(LMIC.bcninfo.txtime + BCN_INTV_osticks)));
}
oidx += 4;
continue;
}
}
EV(specCond, ERR, (e_.reason = EV::specCond_t::BAD_MAC_CMD,
e_.eui = MAIN::CDEV->getEui(),
e_.info = Base::lsbf4(&d[pend]),
e_.info2 = Base::msbf4(&opts[oidx])));
break;
}
if( oidx != olen ) {
EV(specCond, ERR, (e_.reason = EV::specCond_t::CORRUPTED_FRAME,
e_.eui = MAIN::CDEV->getEui(),
e_.info = 0x1000000 + (oidx) + (olen<<8)));
}
if( !replayConf ) {
// Handle payload only if not a replay
// Decrypt payload - if any
if( port >= 0 && pend-poff > 0 )
aes_cipher(port <= 0 ? LMIC.nwkKey : LMIC.artKey, LMIC.devaddr, seqno, /*dn*/1, d+poff, pend-poff);
EV(dfinfo, DEBUG, (e_.deveui = MAIN::CDEV->getEui(),
e_.devaddr = LMIC.devaddr,
e_.seqno = seqno,
e_.flags = (port < 0 ? EV::dfinfo_t::NOPORT : 0) | EV::dfinfo_t::DN,
e_.mic = Base::lsbf4(&d[pend]),
e_.hdr = d[LORA::OFF_DAT_HDR],
e_.fct = d[LORA::OFF_DAT_FCT],
e_.port = port,
e_.plen = dlen,
e_.opts.length = olen,
memcpy(&e_.opts[0], opts, olen)));
} else {
EV(specCond, INFO, (e_.reason = EV::specCond_t::DNSEQNO_REPLAY,
e_.eui = MAIN::CDEV->getEui(),
e_.info = Base::lsbf4(&d[pend]),
e_.info2 = seqno));
}
if( // NWK acks but we don't have a frame pending
(ackup && LMIC.txCnt == 0) ||
// We sent up confirmed and we got a response in DNW1/DNW2
// BUT it did not carry an ACK - this should never happen
// Do not resend and assume frame was not ACKed.
(!ackup && LMIC.txCnt != 0) ) {
EV(specCond, ERR, (e_.reason = EV::specCond_t::SPURIOUS_ACK,
e_.eui = MAIN::CDEV->getEui(),
e_.info = seqno,
e_.info2 = ackup));
}
if( LMIC.txCnt != 0 ) // we requested an ACK
LMIC.txrxFlags |= ackup ? TXRX_ACK : TXRX_NACK;
if( port < 0 ) {
LMIC.txrxFlags |= TXRX_NOPORT;
LMIC.dataBeg = poff;
LMIC.dataLen = 0;
} else {
LMIC.txrxFlags |= TXRX_PORT;
LMIC.dataBeg = poff;
LMIC.dataLen = pend-poff;
}
return 1;
}
// ================================================================================
// TX/RX transaction support
static void setupRx2 (void) {
LMIC.txrxFlags = TXRX_DNW2;
LMIC.rps = dndr2rps(LMIC.dn2Dr);
LMIC.freq = LMIC.dn2Freq;
LMIC.dataLen = 0;
os_radio(RADIO_RX);
}
static void schedRx2 (ostime_t delay, osjobcb_t func) {
// Add 1.5 symbols we need 5 out of 8. Try to sync 1.5 symbols into the preamble.
LMIC.rxtime = LMIC.txend + delay + (PAMBL_SYMS-MINRX_SYMS)*dr2hsym(LMIC.dn2Dr);
os_setTimedCallback(&LMIC.osjob, LMIC.rxtime - RX_RAMPUP, func);
}
static void setupRx1 (osjobcb_t func) {
LMIC.txrxFlags = TXRX_DNW1;
// Turn LMIC.rps from TX over to RX
LMIC.rps = setNocrc(LMIC.rps,1);
LMIC.dataLen = 0;
LMIC.osjob.func = func;
os_radio(RADIO_RX);
}
// Called by HAL once TX complete and delivers exact end of TX time stamp in LMIC.rxtime
static void txDone (ostime_t delay, osjobcb_t func) {
if( (LMIC.opmode & (OP_TRACK|OP_PINGABLE|OP_PINGINI)) == (OP_TRACK|OP_PINGABLE) ) {
rxschedInit(&LMIC.ping); // note: reuses LMIC.frame buffer!
LMIC.opmode |= OP_PINGINI;
}
// Change RX frequency / rps (US only) before we increment txChnl
setRx1Params();
// LMIC.rxsyms carries the TX datarate (can be != LMIC.datarate [confirm retries etc.])
// Setup receive - LMIC.rxtime is preloaded with 1.5 symbols offset to tune
// into the middle of the 8 symbols preamble.
#if defined(CFG_eu868)
if( /* TX datarate */LMIC.rxsyms == DR_FSK ) {
LMIC.rxtime = LMIC.txend + delay - PRERX_FSK*us2osticksRound(160);
LMIC.rxsyms = RXLEN_FSK;
}
else
#endif
{
LMIC.rxtime = LMIC.txend + delay + (PAMBL_SYMS-MINRX_SYMS)*dr2hsym(LMIC.dndr);
LMIC.rxsyms = MINRX_SYMS;
}
os_setTimedCallback(&LMIC.osjob, LMIC.rxtime - RX_RAMPUP, func);
}
// ======================================== Join frames
static void onJoinFailed (xref2osjob_t osjob) {
// Notify app - must call LMIC_reset() to stop joining
// otherwise join procedure continues.
reportEvent(EV_JOIN_FAILED);
}
static bit_t processJoinAccept (void) {
ASSERT(LMIC.txrxFlags != TXRX_DNW1 || LMIC.dataLen != 0);
ASSERT((LMIC.opmode & OP_TXRXPEND)!=0);
if( LMIC.dataLen == 0 ) {
nojoinframe:
if( (LMIC.opmode & OP_JOINING) == 0 ) {
ASSERT((LMIC.opmode & OP_REJOIN) != 0);
// REJOIN attempt for roaming
LMIC.opmode &= ~(OP_REJOIN|OP_TXRXPEND);
if( LMIC.rejoinCnt < 10 )
LMIC.rejoinCnt++;
reportEvent(EV_REJOIN_FAILED);
return 1;
}
LMIC.opmode &= ~OP_TXRXPEND;
ostime_t delay = nextJoinState();
EV(devCond, DEBUG, (e_.reason = EV::devCond_t::NO_JACC,
e_.eui = MAIN::CDEV->getEui(),
e_.info = LMIC.datarate|DR_PAGE,
e_.info2 = osticks2ms(delay)));
// Build next JOIN REQUEST with next engineUpdate call
// Optionally, report join failed.
// Both after a random/chosen amount of ticks.
os_setTimedCallback(&LMIC.osjob, os_getTime()+delay,
(delay&1) != 0
? FUNC_ADDR(onJoinFailed) // one JOIN iteration done and failed
: FUNC_ADDR(runEngineUpdate)); // next step to be delayed
return 1;
}
u1_t hdr = LMIC.frame[0];
u1_t dlen = LMIC.dataLen;
u4_t mic = os_rlsbf4(&LMIC.frame[dlen-4]); // safe before modified by encrypt!
if( (dlen != LEN_JA && dlen != LEN_JAEXT)
|| (hdr & (HDR_FTYPE|HDR_MAJOR)) != (HDR_FTYPE_JACC|HDR_MAJOR_V1) ) {
EV(specCond, ERR, (e_.reason = EV::specCond_t::UNEXPECTED_FRAME,
e_.eui = MAIN::CDEV->getEui(),
e_.info = dlen < 4 ? 0 : mic,
e_.info2 = hdr + (dlen<<8)));
badframe:
if( (LMIC.txrxFlags & TXRX_DNW1) != 0 )
return 0;
goto nojoinframe;
}
aes_encrypt(LMIC.frame+1, dlen-1);
if( !aes_verifyMic0(LMIC.frame, dlen-4) ) {
EV(specCond, ERR, (e_.reason = EV::specCond_t::JOIN_BAD_MIC,
e_.info = mic));
goto badframe;
}
u4_t addr = os_rlsbf4(LMIC.frame+OFF_JA_DEVADDR);
LMIC.devaddr = addr;
LMIC.netid = os_rlsbf4(&LMIC.frame[OFF_JA_NETID]) & 0xFFFFFF;
#if defined(CFG_eu868)
initDefaultChannels(0);
#endif
if( dlen > LEN_JA ) {
dlen = OFF_CFLIST;
#if defined(CFG_eu868)
u1_t chidx=3;
#elif defined(CFG_us915)
u1_t chidx=72;
#endif
for( ; chidx<8; chidx++, dlen+=3 )
LMIC_setupChannel(chidx, convFreq(&LMIC.frame[dlen]), 0, -1);
}
// already incremented when JOIN REQ got sent off
aes_sessKeys(LMIC.devNonce-1, &LMIC.frame[OFF_JA_ARTNONCE], LMIC.nwkKey, LMIC.artKey);
DO_DEVDB(LMIC.netid, netid);
DO_DEVDB(LMIC.devaddr, devaddr);
DO_DEVDB(LMIC.nwkKey, nwkkey);
DO_DEVDB(LMIC.artKey, artkey);
EV(joininfo, INFO, (e_.arteui = MAIN::CDEV->getArtEui(),
e_.deveui = MAIN::CDEV->getEui(),
e_.devaddr = LMIC.devaddr,
e_.oldaddr = oldaddr,
e_.nonce = LMIC.devNonce-1,
e_.mic = mic,
e_.reason = ((LMIC.opmode & OP_REJOIN) != 0
? EV::joininfo_t::REJOIN_ACCEPT
: EV::joininfo_t::ACCEPT)));
ASSERT((LMIC.opmode & (OP_JOINING|OP_REJOIN))!=0);
if( (LMIC.opmode & OP_REJOIN) != 0 ) {
// Lower DR every try below current UP DR
LMIC.datarate = lowerDR(LMIC.datarate, LMIC.rejoinCnt);
}
LMIC.opmode &= ~(OP_JOINING|OP_TRACK|OP_REJOIN|OP_TXRXPEND|OP_PINGINI) | OP_NEXTCHNL;
stateJustJoined();
reportEvent(EV_JOINED);
return 1;
}
static void processRx2Jacc (xref2osjob_t osjob) {
if( LMIC.dataLen == 0 )
LMIC.txrxFlags = 0; // nothing in 1st/2nd DN slot
processJoinAccept();
}
static void setupRx2Jacc (xref2osjob_t osjob) {
LMIC.osjob.func = FUNC_ADDR(processRx2Jacc);
setupRx2();
}
static void processRx1Jacc (xref2osjob_t osjob) {
if( LMIC.dataLen == 0 || !processJoinAccept() )
schedRx2(DELAY_JACC2_osticks, FUNC_ADDR(setupRx2Jacc));
}
static void setupRx1Jacc (xref2osjob_t osjob) {
setupRx1(FUNC_ADDR(processRx1Jacc));
}
static void jreqDone (xref2osjob_t osjob) {
txDone(DELAY_JACC1_osticks, FUNC_ADDR(setupRx1Jacc));
}
// ======================================== Data frames
// Fwd decl.
static bit_t processDnData(void);
static void processRx2DnDataDelay (xref2osjob_t osjob) {
processDnData();
}
static void processRx2DnData (xref2osjob_t osjob) {
if( LMIC.dataLen == 0 ) {
LMIC.txrxFlags = 0; // nothing in 1st/2nd DN slot
// Delay callback processing to avoid up TX while gateway is txing our missed frame!
// Since DNW2 uses SF12 by default we wait 3 secs.
os_setTimedCallback(&LMIC.osjob,
(os_getTime() + DNW2_SAFETY_ZONE + rndDelay(2)),
processRx2DnDataDelay);
return;
}
processDnData();
}
static void setupRx2DnData (xref2osjob_t osjob) {
LMIC.osjob.func = FUNC_ADDR(processRx2DnData);
setupRx2();
}
static void processRx1DnData (xref2osjob_t osjob) {
if( LMIC.dataLen == 0 || !processDnData() )
schedRx2(DELAY_DNW2_osticks, FUNC_ADDR(setupRx2DnData));
}
static void setupRx1DnData (xref2osjob_t osjob) {
setupRx1(FUNC_ADDR(processRx1DnData));
}
static void updataDone (xref2osjob_t osjob) {
txDone(DELAY_DNW1_osticks, FUNC_ADDR(setupRx1DnData));
}
// ========================================
static void buildDataFrame (void) {
bit_t txdata = ((LMIC.opmode & (OP_TXDATA|OP_POLL)) != OP_POLL);
u1_t dlen = txdata ? LMIC.pendTxLen : 0;
// Piggyback MAC options
// Prioritize by importance
int end = OFF_DAT_OPTS;
if( (LMIC.opmode & (OP_TRACK|OP_PINGABLE)) == (OP_TRACK|OP_PINGABLE) ) {
// Indicate pingability in every UP frame
LMIC.frame[end] = MCMD_PING_IND;
LMIC.frame[end+1] = LMIC.ping.dr | (LMIC.ping.intvExp<<4);
end += 2;
}
if( LMIC.dutyCapAns ) {
LMIC.frame[end] = MCMD_DCAP_ANS;
end += 1;
LMIC.dutyCapAns = 0;
}
if( LMIC.dn2Ans ) {
LMIC.frame[end+0] = MCMD_DN2P_ANS;
LMIC.frame[end+1] = LMIC.dn2Ans & ~MCMD_DN2P_ANS_RFU;
end += 2;
LMIC.dn2Ans = 0;
}
if( LMIC.devsAns ) { // answer to device status
LMIC.frame[end+0] = MCMD_DEVS_ANS;
LMIC.frame[end+1] = LMIC.margin;
LMIC.frame[end+2] = os_getBattLevel();
end += 3;
LMIC.devsAns = 0;
}
if( LMIC.ladrAns ) { // answer to ADR change
LMIC.frame[end+0] = MCMD_LADR_ANS;
LMIC.frame[end+1] = LMIC.ladrAns & ~MCMD_LADR_ANS_RFU;
end += 2;
LMIC.ladrAns = 0;
}
if( LMIC.bcninfoTries > 0 ) {
LMIC.frame[end] = MCMD_BCNI_REQ;
end += 1;
}
if( LMIC.adrChanged ) {
if( LMIC.adrAckReq < 0 )
LMIC.adrAckReq = 0;
LMIC.adrChanged = 0;
}
if( LMIC.pingSetAns != 0 ) {
LMIC.frame[end+0] = MCMD_PING_ANS;
LMIC.frame[end+1] = LMIC.pingSetAns & ~MCMD_PING_ANS_RFU;
end += 2;
LMIC.pingSetAns = 0;
}
if( LMIC.snchAns ) {
LMIC.frame[end+0] = MCMD_SNCH_ANS;
LMIC.frame[end+1] = LMIC.snchAns & ~MCMD_SNCH_ANS_RFU;
end += 2;
LMIC.snchAns = 0;
}
ASSERT(end <= OFF_DAT_OPTS+16);
u1_t flen = end + (txdata ? 5+dlen : 4);
if( flen > MAX_LEN_FRAME ) {
// Options and payload too big - delay payload
txdata = 0;
flen = end+4;
}
LMIC.frame[OFF_DAT_HDR] = HDR_FTYPE_DAUP | HDR_MAJOR_V1;
LMIC.frame[OFF_DAT_FCT] = (LMIC.dnConf | LMIC.adrEnabled
| (LMIC.adrAckReq >= 0 ? FCT_ADRARQ : 0)
| (end-OFF_DAT_OPTS));
os_wlsbf4(LMIC.frame+OFF_DAT_ADDR, LMIC.devaddr);
if( LMIC.txCnt == 0 ) {
LMIC.seqnoUp += 1;
DO_DEVDB(LMIC.seqnoUp,seqnoUp);
} else {
EV(devCond, INFO, (e_.reason = EV::devCond_t::RE_TX,
e_.eui = MAIN::CDEV->getEui(),
e_.info = LMIC.seqnoUp-1,
e_.info2 = ((LMIC.txCnt+1) |
(DRADJUST[LMIC.txCnt+1] << 8) |
((LMIC.datarate|DR_PAGE)<<16))));
}
os_wlsbf2(LMIC.frame+OFF_DAT_SEQNO, LMIC.seqnoUp-1);
// Clear pending DN confirmation
LMIC.dnConf = 0;
if( txdata ) {
if( LMIC.pendTxConf ) {
// Confirmed only makes sense if we have a payload (or at least a port)
LMIC.frame[OFF_DAT_HDR] = HDR_FTYPE_DCUP | HDR_MAJOR_V1;
if( LMIC.txCnt == 0 ) LMIC.txCnt = 1;
}
LMIC.frame[end] = LMIC.pendTxPort;
os_copyMem(LMIC.frame+end+1, LMIC.pendTxData, dlen);
aes_cipher(LMIC.pendTxPort==0 ? LMIC.nwkKey : LMIC.artKey,
LMIC.devaddr, LMIC.seqnoUp-1,
/*up*/0, LMIC.frame+end+1, dlen);
}
aes_appendMic(LMIC.nwkKey, LMIC.devaddr, LMIC.seqnoUp-1, /*up*/0, LMIC.frame, flen-4);
EV(dfinfo, DEBUG, (e_.deveui = MAIN::CDEV->getEui(),
e_.devaddr = LMIC.devaddr,
e_.seqno = LMIC.seqnoUp-1,
e_.flags = (LMIC.pendTxPort < 0 ? EV::dfinfo_t::NOPORT : EV::dfinfo_t::NOP),
e_.mic = Base::lsbf4(&LMIC.frame[flen-4]),
e_.hdr = LMIC.frame[LORA::OFF_DAT_HDR],
e_.fct = LMIC.frame[LORA::OFF_DAT_FCT],
e_.port = LMIC.pendTxPort,
e_.plen = txdata ? dlen : 0,
e_.opts.length = end-LORA::OFF_DAT_OPTS,
memcpy(&e_.opts[0], LMIC.frame+LORA::OFF_DAT_OPTS, end-LORA::OFF_DAT_OPTS)));
LMIC.dataLen = flen;
}
// Callback from HAL during scan mode or when job timer expires.
static void onBcnRx (xref2osjob_t job) {
// If we arrive via job timer make sure to put radio to rest.
os_radio(RADIO_RST);
os_clearCallback(&LMIC.osjob);
if( LMIC.dataLen == 0 ) {
// Nothing received - timeout
LMIC.opmode &= ~(OP_SCAN | OP_TRACK);
reportEvent(EV_SCAN_TIMEOUT);
return;
}
if( decodeBeacon() <= 0 ) {
// Something is wrong with the beacon - continue scan
LMIC.dataLen = 0;
os_radio(RADIO_RXON);
os_setTimedCallback(&LMIC.osjob, LMIC.bcninfo.txtime, FUNC_ADDR(onBcnRx));
return;
}
// Found our 1st beacon
// We don't have a previous beacon to calc some drift - assume
// an max error of 13ms = 128sec*100ppm which is roughly +/-100ppm
calcBcnRxWindowFromMillis(13,1);
LMIC.opmode &= ~OP_SCAN; // turn SCAN off
LMIC.opmode |= OP_TRACK; // auto enable tracking
reportEvent(EV_BEACON_FOUND); // can be disabled in callback
}
// Enable receiver to listen to incoming beacons
// netid defines when scan stops (any or specific beacon)
// This mode ends with events: EV_SCAN_TIMEOUT/EV_SCAN_BEACON
// Implicitely cancels any pending TX/RX transaction.
// Also cancels an onpoing joining procedure.
static void startScan (void) {
ASSERT(LMIC.devaddr!=0 && (LMIC.opmode & OP_JOINING)==0);
if( (LMIC.opmode & OP_SHUTDOWN) != 0 )
return;
// Cancel onging TX/RX transaction
LMIC.txCnt = LMIC.dnConf = LMIC.bcninfo.flags = 0;
LMIC.opmode = (LMIC.opmode | OP_SCAN) & ~(OP_TXRXPEND);
setBcnRxParams();
LMIC.rxtime = LMIC.bcninfo.txtime = os_getTime() + sec2osticks(BCN_INTV_sec+1);
os_setTimedCallback(&LMIC.osjob, LMIC.rxtime, FUNC_ADDR(onBcnRx));
os_radio(RADIO_RXON);
}
bit_t LMIC_enableTracking (u1_t tryBcnInfo) {
if( (LMIC.opmode & (OP_SCAN|OP_TRACK|OP_SHUTDOWN)) != 0 )
return 0; // already in progress or failed to enable
// If BCN info requested from NWK then app has to take are
// of sending data up so that MCMD_BCNI_REQ can be attached.
if( (LMIC.bcninfoTries = tryBcnInfo) == 0 )
startScan();
return 1; // enabled
}
void LMIC_disableTracking (void) {
LMIC.opmode &= ~(OP_SCAN|OP_TRACK);
LMIC.bcninfoTries = 0;
engineUpdate();
}
// ================================================================================
//
// Join stuff
//
// ================================================================================
static void buildJoinRequest (u1_t ftype) {
// Do not use pendTxData since we might have a pending
// user level frame in there. Use RX holding area instead.
xref2u1_t d = LMIC.frame;
d[OFF_JR_HDR] = ftype;
os_getArtEui(d + OFF_JR_ARTEUI);
os_getDevEui(d + OFF_JR_DEVEUI);
os_wlsbf2(d + OFF_JR_DEVNONCE, LMIC.devNonce);
aes_appendMic0(d, OFF_JR_MIC);
EV(joininfo,INFO,(e_.deveui = MAIN::CDEV->getEui(),
e_.arteui = MAIN::CDEV->getArtEui(),
e_.nonce = LMIC.devNonce,
e_.oldaddr = LMIC.devaddr,
e_.mic = Base::lsbf4(&d[LORA::OFF_JR_MIC]),
e_.reason = ((LMIC.opmode & OP_REJOIN) != 0
? EV::joininfo_t::REJOIN_REQUEST
: EV::joininfo_t::REQUEST)));
LMIC.dataLen = LEN_JR;
LMIC.devNonce++;
DO_DEVDB(LMIC.devNonce,devNonce);
}
static void startJoining (xref2osjob_t osjob) {
reportEvent(EV_JOINING);
}
// Start join procedure if not already joined.
bit_t LMIC_startJoining (void) {
if( LMIC.devaddr == 0 ) {
// There should be no TX/RX going on
ASSERT((LMIC.opmode & (OP_POLL|OP_TXRXPEND)) == 0);
// Lift any previous duty limitation
LMIC.globalDutyRate = 0;
// Cancel scanning
LMIC.opmode &= ~(OP_SCAN|OP_REJOIN|OP_LINKDEAD|OP_NEXTCHNL);
// Setup state
LMIC.rejoinCnt = LMIC.txCnt = LMIC.pendTxConf = 0;
initJoinLoop();
LMIC.opmode |= OP_JOINING;
// reportEvent will call engineUpdate which then starts sending JOIN REQUESTS
os_setCallback(&LMIC.osjob, FUNC_ADDR(startJoining));
return 1;
}
return 0; // already joined
}
// ================================================================================
//
//
//
// ================================================================================
static void processPingRx (xref2osjob_t osjob) {
if( LMIC.dataLen != 0 ) {
LMIC.txrxFlags = TXRX_PING;
if( decodeFrame() ) {
reportEvent(EV_RXCOMPLETE);
return;
}
}
// Pick next ping slot
engineUpdate();
}
static bit_t processDnData (void) {
ASSERT((LMIC.opmode & OP_TXRXPEND)!=0);
if( LMIC.dataLen == 0 ) {
norx:
if( LMIC.txCnt != 0 ) {
if( LMIC.txCnt < TXCONF_ATTEMPTS ) {
LMIC.txCnt += 1;
setDrTxpow(DRCHG_NOACK, lowerDR(LMIC.datarate, DRADJUST[LMIC.txCnt]), KEEP_TXPOW);
// Schedule another retransmission
txDelay(LMIC.rxtime, RETRY_PERIOD_secs);
LMIC.opmode &= ~OP_TXRXPEND;
engineUpdate();
return 1;
}
LMIC.txrxFlags = TXRX_NACK | TXRX_NOPORT;
} else {
// Nothing received - implies no port
LMIC.txrxFlags = TXRX_NOPORT;
}
if( LMIC.adrAckReq != LINK_CHECK_OFF )
LMIC.adrAckReq += 1;
LMIC.dataBeg = LMIC.dataLen = 0;
txcomplete:
LMIC.opmode &= ~(OP_TXDATA|OP_TXRXPEND);
if( (LMIC.txrxFlags & (TXRX_DNW1|TXRX_DNW2|TXRX_PING)) != 0 && (LMIC.opmode & OP_LINKDEAD) != 0 ) {
LMIC.opmode &= ~OP_LINKDEAD;
reportEvent(EV_LINK_ALIVE);
}
reportEvent(EV_TXCOMPLETE);
// If we haven't heard from NWK in a while although we asked for a sign
// assume link is dead - notify application and keep going
if( LMIC.adrAckReq > LINK_CHECK_DEAD ) {
// We haven't heard from NWK for some time although we
// asked for a response for some time - assume we're disconnected. Lower DR one notch.
EV(devCond, ERR, (e_.reason = EV::devCond_t::LINK_DEAD,
e_.eui = MAIN::CDEV->getEui(),
e_.info = LMIC.adrAckReq));
setDrTxpow(DRCHG_NOADRACK, decDR((dr_t)LMIC.datarate), KEEP_TXPOW);
LMIC.adrAckReq = LINK_CHECK_CONT;
LMIC.opmode |= OP_REJOIN|OP_LINKDEAD;
reportEvent(EV_LINK_DEAD);
}
// If this falls to zero the NWK did not answer our MCMD_BCNI_REQ commands - try full scan
if( LMIC.bcninfoTries > 0 ) {
if( (LMIC.opmode & OP_TRACK) != 0 ) {
reportEvent(EV_BEACON_FOUND);
LMIC.bcninfoTries = 0;
}
else if( --LMIC.bcninfoTries == 0 ) {
startScan(); // NWK did not answer - try scan
}
}
return 1;
}
if( !decodeFrame() ) {
if( (LMIC.txrxFlags & TXRX_DNW1) != 0 )
return 0;
goto norx;
}
goto txcomplete;
}
static void processBeacon (xref2osjob_t osjob) {
ostime_t lasttx = LMIC.bcninfo.txtime; // save here - decodeBeacon might overwrite
u1_t flags = LMIC.bcninfo.flags;
ev_t ev;
if( LMIC.dataLen != 0 && decodeBeacon() >= 1 ) {
ev = EV_BEACON_TRACKED;
if( (flags & (BCN_PARTIAL|BCN_FULL)) == 0 ) {
// We don't have a previous beacon to calc some drift - assume
// an max error of 13ms = 128sec*100ppm which is roughly +/-100ppm
calcBcnRxWindowFromMillis(13,0);
goto rev;
}
// We have a previous BEACON to calculate some drift
s2_t drift = BCN_INTV_osticks - (LMIC.bcninfo.txtime - lasttx);
if( LMIC.missedBcns > 0 ) {
drift = LMIC.drift + (drift - LMIC.drift) / (LMIC.missedBcns+1);
}
if( (LMIC.bcninfo.flags & BCN_NODRIFT) == 0 ) {
s2_t diff = LMIC.drift - drift;
if( diff < 0 ) diff = -diff;
LMIC.lastDriftDiff = diff;
if( LMIC.maxDriftDiff < diff )
LMIC.maxDriftDiff = diff;
LMIC.bcninfo.flags &= ~BCN_NODDIFF;
}
LMIC.drift = drift;
LMIC.missedBcns = LMIC.rejoinCnt = 0;
LMIC.bcninfo.flags &= ~BCN_NODRIFT;
EV(devCond,INFO,(e_.reason = EV::devCond_t::CLOCK_DRIFT,
e_.eui = MAIN::CDEV->getEui(),
e_.info = drift,
e_.info2 = /*occasion BEACON*/0));
ASSERT((LMIC.bcninfo.flags & (BCN_PARTIAL|BCN_FULL)) != 0);
} else {
ev = EV_BEACON_MISSED;
LMIC.bcninfo.txtime += BCN_INTV_osticks - LMIC.drift;
LMIC.bcninfo.time += BCN_INTV_sec;
LMIC.missedBcns++;
// Delay any possible TX after surmised beacon - it's there although we missed it
txDelay(LMIC.bcninfo.txtime + BCN_RESERVE_osticks, 4);
if( LMIC.missedBcns > MAX_MISSED_BCNS )
LMIC.opmode |= OP_REJOIN; // try if we can roam to another network
if( LMIC.bcnRxsyms > MAX_RXSYMS ) {
LMIC.opmode &= ~(OP_TRACK|OP_PINGABLE|OP_PINGINI|OP_REJOIN);
reportEvent(EV_LOST_TSYNC);
return;
}
}
LMIC.bcnRxtime = LMIC.bcninfo.txtime + BCN_INTV_osticks - calcRxWindow(0,DR_BCN);
LMIC.bcnRxsyms = LMIC.rxsyms;
rev:
#if CFG_us915
LMIC.bcnChnl = (LMIC.bcnChnl+1) & 7;
#endif
if( (LMIC.opmode & OP_PINGINI) != 0 )
rxschedInit(&LMIC.ping); // note: reuses LMIC.frame buffer!
reportEvent(ev);
}
static void startRxBcn (xref2osjob_t osjob) {
LMIC.osjob.func = FUNC_ADDR(processBeacon);
os_radio(RADIO_RX);
}
static void startRxPing (xref2osjob_t osjob) {
LMIC.osjob.func = FUNC_ADDR(processPingRx);
os_radio(RADIO_RX);
}
// Decide what to do next for the MAC layer of a device
static void engineUpdate (void) {
// Check for ongoing state: scan or TX/RX transaction
if( (LMIC.opmode & (OP_SCAN|OP_TXRXPEND|OP_SHUTDOWN)) != 0 )
return;
if( LMIC.devaddr == 0 && (LMIC.opmode & OP_JOINING) == 0 ) {
LMIC_startJoining();
return;
}
ostime_t now = os_getTime();
ostime_t rxtime = 0;
ostime_t txbeg = 0;
if( (LMIC.opmode & OP_TRACK) != 0 ) {
// We are tracking a beacon
ASSERT( now + RX_RAMPUP - LMIC.bcnRxtime <= 0 );
rxtime = LMIC.bcnRxtime - RX_RAMPUP;
}
if( (LMIC.opmode & (OP_JOINING|OP_REJOIN|OP_TXDATA|OP_POLL)) != 0 ) {
// Need to TX some data...
// Assuming txChnl points to channel which first becomes available again.
bit_t jacc = ((LMIC.opmode & (OP_JOINING|OP_REJOIN)) != 0 ? 1 : 0);
// Find next suitable channel and return availability time
if( (LMIC.opmode & OP_NEXTCHNL) != 0 ) {
txbeg = LMIC.txend = nextTx(now);
LMIC.opmode &= ~OP_NEXTCHNL;
} else {
txbeg = LMIC.txend;
}
// Delayed TX or waiting for duty cycle?
if( (LMIC.globalDutyRate != 0 || (LMIC.opmode & OP_RNDTX) != 0) && (txbeg - LMIC.globalDutyAvail) < 0 )
txbeg = LMIC.globalDutyAvail;
// If we're tracking a beacon...
// then make sure TX-RX transaction is complete before beacon
if( (LMIC.opmode & OP_TRACK) != 0 &&
txbeg + (jacc ? JOIN_GUARD_osticks : TXRX_GUARD_osticks) - rxtime > 0 ) {
// Not enough time to complete TX-RX before beacon - postpone after beacon.
// In order to avoid clustering of postponed TX right after beacon randomize start!
txDelay(rxtime + BCN_RESERVE_osticks, 16);
txbeg = 0;
goto checkrx;
}
// Earliest possible time vs overhead to setup radio
if( txbeg - (now + TX_RAMPUP) < 0 ) {
// We could send right now!
dr_t txdr = (dr_t)LMIC.datarate;
if( jacc ) {
u1_t ftype;
if( (LMIC.opmode & OP_REJOIN) != 0 ) {
txdr = lowerDR(txdr, LMIC.rejoinCnt);
ftype = HDR_FTYPE_REJOIN;
} else {
ftype = HDR_FTYPE_JREQ;
}
buildJoinRequest(ftype);
LMIC.osjob.func = FUNC_ADDR(jreqDone);
} else {
if( LMIC.seqnoDn >= 0xFFFFFF80 ) {
// Imminent roll over - proactively reset MAC
EV(specCond, INFO, (e_.reason = EV::specCond_t::DNSEQNO_ROLL_OVER,
e_.eui = MAIN::CDEV->getEui(),
e_.info = LMIC.seqnoDn,
e_.info2 = 0));
// Device has to react! NWK will not roll over and just stop sending.
// Thus, we have N frames to detect a possible lock up.
reset:
os_setCallback(&LMIC.osjob, FUNC_ADDR(runReset));
return;
}
if( (LMIC.txCnt==0 && LMIC.seqnoUp == 0xFFFFFFFF) ) {
// Roll over of up seq counter
EV(specCond, ERR, (e_.reason = EV::specCond_t::UPSEQNO_ROLL_OVER,
e_.eui = MAIN::CDEV->getEui(),
e_.info2 = LMIC.seqnoUp));
// Do not run RESET event callback from here!
// App code might do some stuff after send unaware of RESET.
goto reset;
}
buildDataFrame();
LMIC.osjob.func = FUNC_ADDR(updataDone);
}
LMIC.rps = setCr(updr2rps(txdr), (cr_t)LMIC.errcr);
LMIC.dndr = txdr; // carry TX datarate (can be != LMIC.datarate) over to txDone/setupRx1
LMIC.opmode = (LMIC.opmode & ~(OP_POLL|OP_RNDTX)) | OP_TXRXPEND | OP_NEXTCHNL;
updateTx(txbeg);
os_radio(RADIO_TX);
return;
}
// Cannot yet TX
if( (LMIC.opmode & OP_TRACK) == 0 )
goto txdelay; // We don't track the beacon - nothing else to do - so wait for the time to TX
// Consider RX tasks
if( txbeg == 0 ) // zero indicates no TX pending
txbeg += 1; // TX delayed by one tick (insignificant amount of time)
} else {
// No TX pending - no scheduled RX
if( (LMIC.opmode & OP_TRACK) == 0 )
return;
}
// Are we pingable?
checkrx:
if( (LMIC.opmode & OP_PINGINI) != 0 ) {
// One more RX slot in this beacon period?
if( rxschedNext(&LMIC.ping, now+RX_RAMPUP) ) {
if( txbeg != 0 && (txbeg - LMIC.ping.rxtime) < 0 )
goto txdelay;
LMIC.rxsyms = LMIC.ping.rxsyms;
LMIC.rxtime = LMIC.ping.rxtime;
LMIC.freq = LMIC.ping.freq;
LMIC.rps = dndr2rps(LMIC.ping.dr);
LMIC.dataLen = 0;
ASSERT(LMIC.rxtime - now+RX_RAMPUP >= 0 );
os_setTimedCallback(&LMIC.osjob, LMIC.rxtime - RX_RAMPUP, FUNC_ADDR(startRxPing));
return;
}
// no - just wait for the beacon
}
if( txbeg != 0 && (txbeg - rxtime) < 0 )
goto txdelay;
setBcnRxParams();
LMIC.rxsyms = LMIC.bcnRxsyms;
LMIC.rxtime = LMIC.bcnRxtime;
if( now - rxtime >= 0 ) {
LMIC.osjob.func = FUNC_ADDR(processBeacon);
os_radio(RADIO_RX);
return;
}
os_setTimedCallback(&LMIC.osjob, rxtime, FUNC_ADDR(startRxBcn));
return;
txdelay:
EV(devCond, INFO, (e_.reason = EV::devCond_t::TX_DELAY,
e_.eui = MAIN::CDEV->getEui(),
e_.info = osticks2ms(txbeg-now),
e_.info2 = LMIC.seqnoUp-1));
os_setTimedCallback(&LMIC.osjob, txbeg-TX_RAMPUP, FUNC_ADDR(runEngineUpdate));
}
void LMIC_setAdrMode (bit_t enabled) {
LMIC.adrEnabled = enabled ? FCT_ADREN : 0;
}
// Should we have/need an ext. API like this?
void LMIC_setDrTxpow (dr_t dr, s1_t txpow) {
setDrTxpow(DRCHG_SET, dr, txpow);
}
void LMIC_shutdown (void) {
os_clearCallback(&LMIC.osjob);
os_radio(RADIO_RST);
LMIC.opmode |= OP_SHUTDOWN;
}
void LMIC_reset (void) {
EV(devCond, INFO, (e_.reason = EV::devCond_t::LMIC_EV,
e_.eui = MAIN::CDEV->getEui(),
e_.info = EV_RESET));
os_radio(RADIO_RST);
os_clearCallback(&LMIC.osjob);
os_clearMem((xref2u1_t)&LMIC,SIZEOFEXPR(LMIC));
LMIC.devaddr = 0;
LMIC.devNonce = os_getRndU2();
LMIC.opmode = OP_NONE;
LMIC.errcr = CR_4_5;
LMIC.adrEnabled = FCT_ADREN;
LMIC.dn2Dr = DR_DNW2; // we need this for 2nd DN window of join accept
LMIC.dn2Freq = FREQ_DNW2; // ditto
LMIC.ping.freq = FREQ_PING; // defaults for ping
LMIC.ping.dr = DR_PING; // ditto
LMIC.ping.intvExp = 0xFF;
#if defined(CFG_us915)
initDefaultChannels();
#endif
DO_DEVDB(LMIC.devaddr, devaddr);
DO_DEVDB(LMIC.devNonce, devNonce);
DO_DEVDB(LMIC.dn2Dr, dn2Dr);
DO_DEVDB(LMIC.dn2Freq, dn2Freq);
DO_DEVDB(LMIC.ping.freq, pingFreq);
DO_DEVDB(LMIC.ping.dr, pingDr);
DO_DEVDB(LMIC.ping.intvExp, pingIntvExp);
}
void LMIC_init (void) {
LMIC.opmode = OP_SHUTDOWN;
}
void LMIC_clrTxData (void) {
LMIC.opmode &= ~(OP_TXDATA|OP_TXRXPEND|OP_POLL);
LMIC.pendTxLen = 0;
if( (LMIC.opmode & (OP_JOINING|OP_SCAN)) != 0 ) // do not interfere with JOINING
return;
os_clearCallback(&LMIC.osjob);
os_radio(RADIO_RST);
engineUpdate();
}
void LMIC_setTxData (void) {
LMIC.opmode |= OP_TXDATA;
if( (LMIC.opmode & OP_JOINING) == 0 )
LMIC.txCnt = 0; // cancel any ongoing TX/RX retries
engineUpdate();
}
//
int LMIC_setTxData2 (u1_t port, xref2u1_t data, u1_t dlen, u1_t confirmed) {
if( dlen > SIZEOFEXPR(LMIC.pendTxData) )
return -2;
if( data != (xref2u1_t)0 )
os_copyMem(LMIC.pendTxData, data, dlen);
LMIC.pendTxConf = confirmed;
LMIC.pendTxPort = port;
LMIC.pendTxLen = dlen;
LMIC_setTxData();
return 0;
}
// Send a payload-less message to signal device is alive
void LMIC_sendAlive (void) {
LMIC.opmode |= OP_POLL;
engineUpdate();
}
// Check if other networks are around.
void LMIC_tryRejoin (void) {
LMIC.opmode |= OP_REJOIN;
engineUpdate();
}
//! \brief Setup given session keys
//! and put the MAC in a state as if
//! a join request/accept would have negotiated just these keys.
//! It is crucial that the combinations `devaddr/nwkkey` and `devaddr/artkey`
//! are unique within the network identified by `netid`.
//! NOTE: on Harvard architectures when session keys are in flash:
//! Caller has to fill in LMIC.{nwk,art}Key before and pass {nwk,art}Key are NULL
//! \param netid a 24 bit number describing the network id this device is using
//! \param devaddr the 32 bit session address of the device. It is strongly recommended
//! to ensure that different devices use different numbers with high probability.
//! \param nwkKey the 16 byte network session key used for message integrity.
//! If NULL the caller has copied the key into `LMIC.nwkKey` before.
//! \param artKey the 16 byte application router session key used for message confidentiality.
//! If NULL the caller has copied the key into `LMIC.artKey` before.
void LMIC_setSession (u4_t netid, devaddr_t devaddr, xref2u1_t nwkKey, xref2u1_t artKey) {
LMIC.netid = netid;
LMIC.devaddr = devaddr;
if( nwkKey != (xref2u1_t)0 )
os_copyMem(LMIC.nwkKey, nwkKey, 16);
if( artKey != (xref2u1_t)0 )
os_copyMem(LMIC.artKey, artKey, 16);
#if defined(CFG_eu868)
initDefaultChannels(0);
#endif
LMIC.opmode &= ~(OP_JOINING|OP_TRACK|OP_REJOIN|OP_TXRXPEND|OP_PINGINI);
LMIC.opmode |= OP_NEXTCHNL;
stateJustJoined();
}
// Enable/disable link check validation.
// LMIC sets the ADRACKREQ bit in UP frames if there were no DN frames
// for a while. It expects the network to provide a DN message to prove
// connectivity with a span of UP frames. If this no such prove is coming
// then the datarate is lowered and a LINK_DEAD event is generated.
// This mode can be disabled and no connectivity prove (ADRACKREQ) is requested
// nor is the datarate changed.
// This must be called only if a session is established (e.g. after EV_JOINED)
void LMIC_setLinkCheckMode (bit_t enabled) {
LMIC.adrChanged = 0;
LMIC.adrAckReq = enabled ? LINK_CHECK_INIT : LINK_CHECK_OFF;
}