IBM LoRa MAC in C (LMiC) mbed library port

Dependents:   lora-temperature LoRaWAN-lmic-app_HS LoRaWAN-lmic-app_huynh

LoRa WAN in C for sx1276 shield

Currently version 1.5


LoRaWAN network configuration for end-device

The following three pieces of information uniquely identifies end-device to network to allow over-the-air activation. These are stored in the end-device prior to join procedure.

AppEUI

Uniquely identifies application provider of end-device.

Least-significant byte first, 8 bytes, use reverse memcpy() to keep same order as shown on lora server.

example C code

static const u1_t APPEUI[8]  = { 0x01, 0x00, 0x01, 0x00, 0x00, 0x0C, 0x25, 0x00 };

This is copied into LMIC by os_getArtEui() callback function in application.

DevEUI

End-device ID, unique to each end-node.

Least-significant byte first, 8 bytes, use reverse memcpy() to keep same order as shown on lora server.

example C code

static const u1_t DEVEUI[8]  = { 0x00, 0x00, 0x00, 0x00, 0x01, 0x0C, 0x25, 0x00 }; 

This is copied into LMIC by os_getDevEui() callback function in application.

AppKey (aka DevKey)

128-bit (16byte) AES key.

example C code

static const u1_t DEVKEY[16] = { 0xe4, 0x72, 0x71, 0xc5, 0xf5, 0x30, 0xa9, 0x9f, 0xcf, 0xc4, 0x0e, 0xab, 0xea, 0xd7, 0x19, 0x42 };

This is copied into LMIC by os_getDevKey() callback function in application.

Using over-the air activation, the end-device (LMIC) performs a join procedure every time it starts for first time, or has lost session context information. When join procedure has successfully completed, the end-device will have a network session key (NwkSKey) and an application session key (AppSKey), which are used for encryption and message integrity check.


US915 configuration with http://us01-iot.semtech.com/

  • log in to server
  • click on Applications
  • find your application and click it
  • go to configure motes
  • to create a mote, you may enter a new DevEUI
    • you may copy-paste the 16byte application key from an already existing mote, if you desire.
CHNL_HYBRID125KHz500KHz
defined valuechannelschannel
00 to 764
18 to 1565
216 to 2366
324 to 3167
432 to 3968
540 to 4769
648 to 5570
756 to 6371
undef0 to 6364 to 71
Revision:
0:62d1edcc13d1
Child:
1:d3b7bde3995c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lorabase.h	Thu Jan 22 12:50:49 2015 +0000
@@ -0,0 +1,372 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#ifndef _lorabase_h_
+#define _lorabase_h_
+
+// ================================================================================
+// BEG: Keep in sync with lorabase.hpp
+//
+
+enum _cr_t { CR_4_5=0, CR_4_6, CR_4_7, CR_4_8 };
+enum _sf_t { FSK=0, SF7, SF8, SF9, SF10, SF11, SF12, SFrfu };
+enum _bw_t { BW125=0, BW250, BW500, BWrfu };
+typedef u1_t cr_t;
+typedef u1_t sf_t;
+typedef u1_t bw_t;
+typedef u1_t dr_t;
+// Radio parameter set (encodes SF/BW/CR/IH/NOCRC)
+typedef u2_t rps_t;
+TYPEDEF_xref2rps_t;
+
+enum { ILLEGAL_RPS = 0xFF };
+enum { DR_PAGE_EU868 = 0x00 };
+enum { DR_PAGE_US915 = 0x10 };
+
+// Global maximum frame length
+enum { STD_PREAMBLE_LEN  =  8 };
+enum { MAX_LEN_FRAME     = 64 };
+enum { LEN_DEVNONCE      =  2 };
+enum { LEN_ARTNONCE      =  3 };
+enum { LEN_NETID         =  3 };
+enum { DELAY_JACC1       =  5 }; // in secs
+enum { DELAY_DNW1        =  1 }; // in secs down window #1
+enum { DELAY_EXTDNW2     =  1 }; // in secs
+enum { DELAY_JACC2       =  DELAY_JACC1+(int)DELAY_EXTDNW2 }; // in secs
+enum { DELAY_DNW2        =  DELAY_DNW1 +(int)DELAY_EXTDNW2 }; // in secs down window #1
+enum { BCN_INTV_exp      = 7 };
+enum { BCN_INTV_sec      = 1<<BCN_INTV_exp };
+enum { BCN_INTV_ms       = BCN_INTV_sec*1000L };
+enum { BCN_INTV_us       = BCN_INTV_ms*1000L };
+enum { BCN_RESERVE_ms    = 2120 };   // space reserved for beacon and NWK management
+enum { BCN_GUARD_ms      = 3000 };   // end of beacon period to prevent interference with beacon
+enum { BCN_SLOT_SPAN_ms  =   30 };   // 2^12 reception slots a this span
+enum { BCN_WINDOW_ms     = BCN_INTV_ms-(int)BCN_GUARD_ms-(int)BCN_RESERVE_ms };
+enum { BCN_RESERVE_us    = 2120000 };
+enum { BCN_GUARD_us      = 3000000 };
+enum { BCN_SLOT_SPAN_us  =   30000 };
+
+#if CFG_eu868 // ==============================================
+
+enum _dr_eu868_t { DR_SF12=0, DR_SF11, DR_SF10, DR_SF9, DR_SF8, DR_SF7, DR_SF7B, DR_FSK, DR_NONE };
+enum { DR_DFLTMIN = DR_SF7 };
+enum { DR_PAGE = DR_PAGE_EU868 };
+
+// Default frequency plan for EU 868MHz ISM band
+// Bands:
+//  g1 :   1%  14dBm  
+//  g2 : 0.1%  14dBm  
+//  g3 :  10%  27dBm  
+//                 freq             band     datarates
+enum { EU868_F1 = 868100000,      // g1   SF7-12 
+       EU868_F2 = 868300000,      // g1   SF7-12 FSK SF7/250         
+       EU868_F3 = 868500000,      // g1   SF7-12         
+       EU868_F4 = 868850000,      // g2   SF7-12         
+       EU868_F5 = 869050000,      // g2   SF7-12         
+       EU868_F6 = 869525000,      // g3   SF7-12         
+       EU868_J4 = 864100000,      // g2   SF7-12  used during join
+       EU868_J5 = 864300000,      // g2   SF7-12   ditto
+       EU868_J6 = 864500000,      // g2   SF7-12   ditto
+};
+enum { EU868_FREQ_MIN = 863000000,
+       EU868_FREQ_MAX = 870000000 };
+
+enum { CHNL_PING         = 5 };
+enum { FREQ_PING         = EU868_F6 };  // default ping freq
+enum { DR_PING           = SF9 };       // default ping DR
+enum { CHNL_DNW2         = 5 };
+enum { FREQ_DNW2         = EU868_F6 };
+enum { DR_DNW2           = DR_SF9 };
+enum { CHNL_BCN          = 5 };
+enum { FREQ_BCN          = EU868_F6 };
+enum { DR_BCN            = DR_SF9 };
+enum { AIRTIME_BCN       = 185344 };  // micros
+
+#elif CFG_us915  // =========================================
+
+enum _dr_us915_t { DR_SF10=0, DR_SF9, DR_SF8, DR_SF7, DR_SF8C, DR_NONE,
+           // Devices behind a router:
+           DR_SF12CR=8, DR_SF11CR, DR_SF10CR, DR_SF9CR, DR_SF8CR, DR_SF7CR };
+enum { DR_DFLTMIN = DR_SF8C };
+enum { DR_PAGE = DR_PAGE_US915 };
+
+// Default frequency plan for US 915MHz
+enum { US915_125kHz_UPFBASE = 902300000,
+       US915_125kHz_UPFSTEP =    200000,
+       US915_500kHz_UPFBASE = 903000000,
+       US915_500kHz_UPFSTEP =   1600000,
+       US915_500kHz_DNFBASE = 923300000,
+       US915_500kHz_DNFSTEP =    600000
+};
+enum { US915_FREQ_MIN = 902000000,
+       US915_FREQ_MAX = 928000000 };
+
+enum { CHNL_PING         = 2 };
+enum { FREQ_PING         = US915_500kHz_DNFBASE + CHNL_PING*US915_500kHz_DNFSTEP };  // default ping freq
+enum { DR_PING           = DR_SF10CR };       // default ping DR
+enum { CHNL_DNW2         = 1 };
+enum { FREQ_DNW2         = US915_500kHz_DNFBASE + CHNL_DNW2*US915_500kHz_DNFSTEP };
+enum { DR_DNW2           = DR_SF10CR };
+enum { CHNL_BCN          = 0 };
+enum { FREQ_BCN          = US915_500kHz_DNFBASE + CHNL_BCN*US915_500kHz_DNFSTEP };
+enum { DR_BCN            = DR_SF10CR };
+enum { AIRTIME_BCN       = 82432 };  // micros
+
+#endif // ===================================================
+
+
+enum {
+    // Beacon frame format
+    OFF_BCN_RFU      = 0,
+    OFF_BCN_NETID    = 4,         
+    OFF_BCN_CMAP     = 7,
+    OFF_BCN_TIME     = 9,
+    OFF_BCN_CRC1     = 13,
+    OFF_BCN_INFO     = 15,
+    OFF_BCN_LAT      = 16,
+    OFF_BCN_LON      = 19,
+    OFF_BCN_CRC2     = 22,
+    LEN_BCN          = 24
+};
+enum {
+    // Join Request frame format
+    OFF_JR_HDR      = 0,
+    OFF_JR_ARTEUI   = 1,
+    OFF_JR_DEVEUI   = 9,
+    OFF_JR_DEVNONCE = 17,
+    OFF_JR_MIC      = 19,
+    LEN_JR          = 23
+};
+enum {
+    // Join Accept frame format
+    OFF_JA_HDR      = 0,
+    OFF_JA_ARTNONCE = 1,
+    OFF_JA_NETID    = 4,
+    OFF_JA_DEVADDR  = 7,
+    OFF_JA_RFU      = 11,
+    OFF_CFLIST      = 14,
+    LEN_JA          = 17,
+    LEN_JAEXT       = 17+16
+};
+enum {
+    // Data frame format
+    OFF_DAT_HDR      = 0,
+    OFF_DAT_ADDR     = 1,
+    OFF_DAT_FCT      = 5,
+    OFF_DAT_SEQNO    = 6,
+    OFF_DAT_OPTS     = 8,
+};
+enum { MAX_LEN_PAYLOAD = MAX_LEN_FRAME-(int)OFF_DAT_OPTS-4 };
+enum {
+    // Bitfields in frame format octet
+    HDR_FTYPE   = 0xE0,
+    HDR_RFU     = 0x1C,
+    HDR_MAJOR   = 0x03
+};
+enum { HDR_FTYPE_DNFLAG = 0x20 };  // flags DN frame except for HDR_FTYPE_PROP
+enum {
+    // Values of frame type bit field
+    HDR_FTYPE_JREQ   = 0x00,
+    HDR_FTYPE_JACC   = 0x20,
+    HDR_FTYPE_DAUP   = 0x40,  // data (unconfirmed) up
+    HDR_FTYPE_DADN   = 0x60,  // data (unconfirmed) dn
+    HDR_FTYPE_DCUP   = 0x80,  // data confirmed up
+    HDR_FTYPE_DCDN   = 0xA0,  // data confirmed dn
+    HDR_FTYPE_REJOIN = 0xC0,  // rejoin for roaming
+    HDR_FTYPE_PROP   = 0xE0
+};
+enum {
+    HDR_MAJOR_V1 = 0x00,
+};
+enum {
+    // Bitfields in frame control octet
+    FCT_ADREN  = 0x80,
+    FCT_ADRARQ = 0x40,
+    FCT_ACK    = 0x20,
+    FCT_MORE   = 0x10,
+    FCT_OPTLEN = 0x0F,
+};
+enum {
+    NWKID_MASK = (int)0xFE000000,
+    NWKID_BITS = 7
+};
+
+// MAC uplink commands   downwlink too
+enum {
+    // Class A
+    MCMD_LCHK_REQ = 0x02, // -  link check request : -
+    MCMD_LADR_ANS = 0x03, // -  link ADR answer    : u1:7-3:RFU, 3/2/1: pow/DR/Ch ACK
+    MCMD_DCAP_ANS = 0x04, // -  duty cycle answer  : -
+    MCMD_DN2P_ANS = 0x05, // -  2nd DN slot status : u1:7-2:RFU  1/0:datarate/channel ack
+    MCMD_DEVS_ANS = 0x06, // -  device status ans  : u1:battery 0,1-254,255=?, u1:7-6:RFU,5-0:margin(-32..31)
+    MCMD_SNCH_ANS = 0x07, // -  set new channel    : u1: 7-2=RFU, 1/0:DR/freq ACK
+    // Class B
+    MCMD_PING_IND = 0x10, // -  pingability indic  : u1: 7=RFU, 6-4:interval, 3-0:datarate
+    MCMD_PING_ANS = 0x11, // -  ack ping freq      : u1: 7-1:RFU, 0:freq ok
+    MCMD_BCNI_REQ = 0x12, // -  next beacon start  : -
+};
+
+// MAC downlink commands
+enum {
+    // Class A
+    MCMD_LCHK_ANS = 0x02, // link check answer  : u1:margin 0-254,255=unknown margin / u1:gwcnt
+    MCMD_LADR_REQ = 0x03, // link ADR request   : u1:DR/TXPow, u2:chmask, u1:chpage/repeat
+    MCMD_DCAP_REQ = 0x04, // duty cycle cap     : u1:255 dead [7-4]:RFU, [3-0]:cap 2^-k
+    MCMD_DN2P_SET = 0x05, // 2nd DN window param: u1:7-4:RFU/3-0:datarate, u3:freq
+    MCMD_DEVS_REQ = 0x06, // device status req  : -
+    MCMD_SNCH_REQ = 0x07, // set new channel    : u1:chidx, u3:freq, u1:DRrange
+    // Class B
+    MCMD_PING_SET = 0x11, // set ping freq      : u3: freq
+    MCMD_BCNI_ANS = 0x12, // next beacon start  : u2: delay(10ms), u1:channel
+};
+
+enum {
+    MCMD_LADR_ANS_RFU    = 0xF8, // RFU bits
+    MCMD_LADR_ANS_POWACK = 0x04, // 0=not supported power level
+    MCMD_LADR_ANS_DRACK  = 0x02, // 0=unknown data rate
+    MCMD_LADR_ANS_CHACK  = 0x01, // 0=unknown channel enabled
+};
+enum {
+    MCMD_DN2P_ANS_RFU    = 0xFC, // RFU bits
+    MCMD_DN2P_ANS_DRACK  = 0x02, // 0=unknown data rate
+    MCMD_DN2P_ANS_CHACK  = 0x01, // 0=unknown channel enabled
+};
+enum {
+    MCMD_SNCH_ANS_RFU    = 0xFC, // RFU bits
+    MCMD_SNCH_ANS_DRACK  = 0x02, // 0=unknown data rate
+    MCMD_SNCH_ANS_FQACK  = 0x01, // 0=rejected channel frequency
+};
+enum {
+    MCMD_PING_ANS_RFU   = 0xFE,
+    MCMD_PING_ANS_FQACK = 0x01
+};
+
+enum {
+    MCMD_DEVS_EXT_POWER   = 0x00, // external power supply
+    MCMD_DEVS_BATT_MIN    = 0x01, // min battery value
+    MCMD_DEVS_BATT_MAX    = 0xFE, // max battery value
+    MCMD_DEVS_BATT_NOINFO = 0xFF, // unknown battery level
+};
+
+// Bit fields byte#3 of MCMD_LADR_REQ payload
+enum {
+    MCMD_LADR_CHP_125ON   = 0x60,  // special channel page enable, bits applied to 64..71
+    MCMD_LADR_CHP_125OFF  = 0x70,  //  ditto
+    MCMD_LADR_N3RFU_MASK  = 0x80,
+    MCMD_LADR_CHPAGE_MASK = 0xF0,
+    MCMD_LADR_REPEAT_MASK = 0x0F,
+    MCMD_LADR_REPEAT_1    = 0x01,
+    MCMD_LADR_CHPAGE_1    = 0x10
+};
+// Bit fields byte#0 of MCMD_LADR_REQ payload
+enum {
+    MCMD_LADR_DR_MASK    = 0xF0,
+    MCMD_LADR_POW_MASK   = 0x0F,
+    MCMD_LADR_DR_SHIFT   = 4,
+    MCMD_LADR_POW_SHIFT  = 0,
+#if CFG_eu868
+    MCMD_LADR_SF12      = DR_SF12<<4,
+    MCMD_LADR_SF11      = DR_SF11<<4,
+    MCMD_LADR_SF10      = DR_SF10<<4,
+    MCMD_LADR_SF9       = DR_SF9 <<4,
+    MCMD_LADR_SF8       = DR_SF8 <<4,
+    MCMD_LADR_SF7       = DR_SF7 <<4,
+    MCMD_LADR_SF7B      = DR_SF7B<<4,
+    MCMD_LADR_FSK       = DR_FSK <<4,
+
+    MCMD_LADR_20dBm     = 0,
+    MCMD_LADR_14dBm     = 1,
+    MCMD_LADR_11dBm     = 2,
+    MCMD_LADR_8dBm      = 3,
+    MCMD_LADR_5dBm      = 4,
+    MCMD_LADR_2dBm      = 5,
+#elif CFG_us915
+    MCMD_LADR_SF10      = DR_SF10<<4,
+    MCMD_LADR_SF9       = DR_SF9 <<4,
+    MCMD_LADR_SF8       = DR_SF8 <<4,
+    MCMD_LADR_SF7       = DR_SF7 <<4,
+    MCMD_LADR_SF8C      = DR_SF8C<<4,
+    MCMD_LADR_SF12CR    = DR_SF12CR<<4,
+    MCMD_LADR_SF11CR    = DR_SF11CR<<4,
+    MCMD_LADR_SF10CR    = DR_SF10CR<<4,
+    MCMD_LADR_SF9CR     = DR_SF9CR<<4,
+    MCMD_LADR_SF8CR     = DR_SF8CR<<4,
+    MCMD_LADR_SF7CR     = DR_SF7CR<<4,
+
+    MCMD_LADR_30dBm     = 0,
+    MCMD_LADR_28dBm     = 1,
+    MCMD_LADR_26dBm     = 2,
+    MCMD_LADR_24dBm     = 3,
+    MCMD_LADR_22dBm     = 4,
+    MCMD_LADR_20dBm     = 5,
+    MCMD_LADR_18dBm     = 6,
+    MCMD_LADR_16dBm     = 7,
+    MCMD_LADR_14dBm     = 8,
+    MCMD_LADR_12dBm     = 9,
+    MCMD_LADR_10dBm     = 10
+#endif
+};
+
+// Device address
+typedef u4_t devaddr_t;
+
+
+// RX quality (device)
+enum { RSSI_OFF=64, SNR_SCALEUP=4 };
+struct rxqu_t {
+    s1_t rssi;    // offset by RSSI_OFF, max physical RSSI range -198..+63
+    s1_t snr;     // scaled by SNR_SCALEUP, max physical SNR range -32..+31.75
+};
+TYPEDEF_xref2rxqu_t;
+
+
+inline sf_t  getSf   (rps_t params)            { return   (sf_t)(params &  0x7); }
+inline rps_t setSf   (rps_t params, sf_t sf)   { return (rps_t)((params & ~0x7) | sf); }
+inline bw_t  getBw   (rps_t params)            { return  (bw_t)((params >> 3) & 0x3); }
+inline rps_t setBw   (rps_t params, bw_t cr)   { return (rps_t)((params & ~0x18) | (cr<<3)); }
+inline cr_t  getCr   (rps_t params)            { return  (cr_t)((params >> 5) & 0x3); }
+inline rps_t setCr   (rps_t params, cr_t cr)   { return (rps_t)((params & ~0x60) | (cr<<5)); }
+inline int   getNocrc(rps_t params)            { return        ((params >> 7) & 0x1); }
+inline rps_t setNocrc(rps_t params, int nocrc) { return (rps_t)((params & ~0x80) | (nocrc<<7)); }
+inline int   getIh   (rps_t params)            { return        ((params >> 8) & 0xFF); }
+inline rps_t setIh   (rps_t params, int ih)    { return (rps_t)((params & ~0xFF00) | (ih<<8)); }
+inline rps_t makeRps (sf_t sf, bw_t bw, cr_t cr, int ih, int nocrc) {
+    return sf | (bw<<3) | (cr<<5) | (nocrc?(1<<7):0) | ((ih&0xFF)<<8);
+}
+#define MAKERPS(sf,bw,cr,ih,nocrc) ((rps_t)((sf) | ((bw)<<3) | ((cr)<<5) | ((nocrc)?(1<<7):0) | ((ih&0xFF)<<8)))
+// Two frames with params r1/r2 would interfere on air: same SFx + BWx 
+inline int sameSfBw(rps_t r1, rps_t r2) { return ((r1^r2)&0x1F) == 0; }
+
+extern const u1_t _DR2RPS_CRC[];
+inline rps_t updr2rps (dr_t dr) { return (rps_t)_DR2RPS_CRC[dr+1]; }
+inline rps_t dndr2rps (dr_t dr) { return setNocrc(updr2rps(dr),1); }
+inline int isFasterDR (dr_t dr1, dr_t dr2) { return dr1 > dr2; }
+inline int isSlowerDR (dr_t dr1, dr_t dr2) { return dr1 < dr2; }
+inline dr_t  incDR    (dr_t dr) { return _DR2RPS_CRC[dr+2]==ILLEGAL_RPS ? dr : (dr_t)(dr+1); } // increase data rate
+inline dr_t  decDR    (dr_t dr) { return _DR2RPS_CRC[dr  ]==ILLEGAL_RPS ? dr : (dr_t)(dr-1); } // decrease data rate
+inline dr_t  assertDR (dr_t dr) { return _DR2RPS_CRC[dr+1]==ILLEGAL_RPS ? DR_DFLTMIN : dr; }   // force into a valid DR
+inline bit_t validDR  (dr_t dr) { return _DR2RPS_CRC[dr+1]!=ILLEGAL_RPS; } // in range
+inline dr_t  lowerDR  (dr_t dr, u1_t n) { while(n--){dr=decDR(dr);} return dr; } // decrease data rate by n steps
+
+//
+// BEG: Keep in sync with lorabase.hpp
+// ================================================================================
+
+
+// Convert between dBm values and power codes (MCMD_LADR_XdBm)
+s1_t pow2dBm (u1_t mcmd_ladr_p1);
+// Calculate airtime
+ostime_t calcAirTime (rps_t rps, u1_t plen);
+// Sensitivity at given SF/BW
+int getSensitivity (rps_t rps);
+
+
+#endif // _lorabase_h_