Diff: vendor/NXP/LPC1768/hal/can_api.c

Revision:

13:0645d8841f51

Parent:

12:5fa2273de5db

Child:

14:096882eb0961

--- a/vendor/NXP/LPC1768/hal/can_api.c	Wed Jul 24 11:11:21 2013 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,300 +0,0 @@
-/* mbed Microcontroller Library
- * Copyright (c) 2006-2013 ARM Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#include "can_api.h"
-
-#include "cmsis.h"
-#include "pinmap.h"
-#include "error.h"
-
-#include <math.h>
-#include <string.h>
-
-/* Acceptance filter mode in AFMR register */
-#define ACCF_OFF                0x01
-#define ACCF_BYPASS             0x02
-#define ACCF_ON                 0x00
-#define ACCF_FULLCAN            0x04
-
-/* There are several bit timing calculators on the internet.
-http://www.port.de/engl/canprod/sv_req_form.html
-http://www.kvaser.com/can/index.htm
-*/
-
-static const PinMap PinMap_CAN_RD[] = {
-    {P0_0 , CAN_1, 1},
-    {P0_4 , CAN_2, 2},
-    {P0_21, CAN_1, 3},
-    {P2_7 , CAN_2, 1},
-    {NC   , NC   , 0}
-};
-
-static const PinMap PinMap_CAN_TD[] = {
-    {P0_1 , CAN_1, 1},
-    {P0_5 , CAN_2, 2},
-    {P0_22, CAN_1, 3},
-    {P2_8 , CAN_2, 1},
-    {NC   , NC   , 0}
-};
-
-// Type definition to hold a CAN message
-struct CANMsg {
-    unsigned int  reserved1 : 16;
-    unsigned int  dlc       :  4; // Bits 16..19: DLC - Data Length Counter
-    unsigned int  reserved0 : 10;
-    unsigned int  rtr       :  1; // Bit 30: Set if this is a RTR message
-    unsigned int  type      :  1; // Bit 31: Set if this is a 29-bit ID message
-    unsigned int  id;             // CAN Message ID (11-bit or 29-bit)
-    unsigned char data[8];        // CAN Message Data Bytes 0-7
-};
-typedef struct CANMsg CANMsg;
-
-static uint32_t can_disable(can_t *obj) {
-    uint32_t sm = obj->dev->MOD;
-    obj->dev->MOD |= 1;
-    return sm;
-}
-
-static inline void can_enable(can_t *obj) {
-    if (obj->dev->MOD & 1) {
-        obj->dev->MOD &= ~(1);
-    }
-}
-
-static int can_pclk(can_t *obj) {
-    int value = 0;
-    switch ((int)obj->dev) {
-        case CAN_1: value = (LPC_SC->PCLKSEL0 & (0x3 << 26)) >> 26; break;
-        case CAN_2: value = (LPC_SC->PCLKSEL0 & (0x3 << 28)) >> 28; break;
-    }
-
-    switch (value) {
-        case 1: return 1;
-        case 2: return 2;
-        case 3: return 6;
-        default: return 4;
-    }
-}
-
-// This table has the sampling points as close to 75% as possible. The first
-// value is TSEG1, the second TSEG2.
-static const int timing_pts[23][2] = {
-    {0x0, 0x0},      // 2,  50%
-    {0x1, 0x0},      // 3,  67%
-    {0x2, 0x0},      // 4,  75%
-    {0x3, 0x0},      // 5,  80%
-    {0x3, 0x1},      // 6,  67%
-    {0x4, 0x1},      // 7,  71%
-    {0x5, 0x1},      // 8,  75%
-    {0x6, 0x1},      // 9,  78%
-    {0x6, 0x2},      // 10, 70%
-    {0x7, 0x2},      // 11, 73%
-    {0x8, 0x2},      // 12, 75%
-    {0x9, 0x2},      // 13, 77%
-    {0x9, 0x3},      // 14, 71%
-    {0xA, 0x3},      // 15, 73%
-    {0xB, 0x3},      // 16, 75%
-    {0xC, 0x3},      // 17, 76%
-    {0xD, 0x3},      // 18, 78%
-    {0xD, 0x4},      // 19, 74%
-    {0xE, 0x4},      // 20, 75%
-    {0xF, 0x4},      // 21, 76%
-    {0xF, 0x5},      // 22, 73%
-    {0xF, 0x6},      // 23, 70%
-    {0xF, 0x7},      // 24, 67%
-};
-
-static unsigned int can_speed(unsigned int sclk, unsigned int pclk, unsigned int cclk, unsigned char psjw) {
-    uint32_t    btr;
-    uint16_t    brp = 0;
-    uint32_t    calcbit;
-    uint32_t    bitwidth;
-    int         hit = 0;
-    int         bits;
-    
-    bitwidth = sclk / (pclk * cclk);
-    
-    brp = bitwidth / 0x18;
-    while ((!hit) && (brp < bitwidth / 4)) {
-        brp++;
-        for (bits = 22; bits > 0; bits--) {
-            calcbit = (bits + 3) * (brp + 1);
-            if (calcbit == bitwidth) {
-                hit = 1;
-                break;
-            }
-        }
-    }
-    
-    if (hit) {
-        btr = ((timing_pts[bits][1] << 20) & 0x00700000)
-            | ((timing_pts[bits][0] << 16) & 0x000F0000)
-            | ((psjw                << 14) & 0x0000C000)
-            | ((brp                 <<  0) & 0x000003FF);
-    } else {
-        btr = 0xFFFFFFFF;
-    }
-    
-    return btr;
-
-}
-
-void can_init(can_t *obj, PinName rd, PinName td) {
-    CANName can_rd = (CANName)pinmap_peripheral(rd, PinMap_CAN_RD);
-    CANName can_td = (CANName)pinmap_peripheral(td, PinMap_CAN_TD);
-    obj->dev = (LPC_CAN_TypeDef *)pinmap_merge(can_rd, can_td);
-    if ((int)obj->dev == NC) {
-        error("CAN pin mapping failed");
-    }
-
-    switch ((int)obj->dev) {
-        case CAN_1: LPC_SC->PCONP |= 1 << 13; break;
-        case CAN_2: LPC_SC->PCONP |= 1 << 14; break;
-    }
-
-    pinmap_pinout(rd, PinMap_CAN_RD);
-    pinmap_pinout(td, PinMap_CAN_TD);
-
-    can_reset(obj);
-    obj->dev->IER = 0;             // Disable Interrupts
-    can_frequency(obj, 100000);
-
-    LPC_CANAF->AFMR = ACCF_BYPASS; // Bypass Filter
-}
-
-void can_free(can_t *obj) {
-    switch ((int)obj->dev) {
-        case CAN_1: LPC_SC->PCONP &= ~(1 << 13); break;
-        case CAN_2: LPC_SC->PCONP &= ~(1 << 14); break;
-    }
-}
-
-int can_frequency(can_t *obj, int f) {
-    int pclk = can_pclk(obj);
-    
-    int btr = can_speed(SystemCoreClock, pclk, (unsigned int)f, 1);
-
-    if (btr > 0) {
-        uint32_t modmask = can_disable(obj);
-        obj->dev->BTR = btr;
-        obj->dev->MOD = modmask;
-        return 1;
-    } else {
-        return 0;
-    }
-}
-
-int can_write(can_t *obj, CAN_Message msg, int cc) {
-    unsigned int CANStatus;
-    CANMsg m;
-
-    can_enable(obj);
-
-    m.id   = msg.id ;
-    m.dlc  = msg.len & 0xF;
-    m.rtr  = msg.type;
-    m.type = msg.format;
-    memcpy(m.data, msg.data, msg.len);
-    const unsigned int *buf = (const unsigned int *)&m;
-
-    CANStatus = obj->dev->SR;
-    if (CANStatus & 0x00000004) {
-        obj->dev->TFI1 = buf[0] & 0xC00F0000;
-        obj->dev->TID1 = buf[1];
-        obj->dev->TDA1 = buf[2];
-        obj->dev->TDB1 = buf[3];
-        if(cc) {
-            obj->dev->CMR = 0x30;
-        } else {
-            obj->dev->CMR = 0x21;
-        }
-        return 1;
-
-    } else if (CANStatus & 0x00000400) {
-        obj->dev->TFI2 = buf[0] & 0xC00F0000;
-        obj->dev->TID2 = buf[1];
-        obj->dev->TDA2 = buf[2];
-        obj->dev->TDB2 = buf[3];
-        if (cc) {
-            obj->dev->CMR = 0x50;
-        } else {
-            obj->dev->CMR = 0x41;
-        }
-        return 1;
-
-    } else if (CANStatus & 0x00040000) {
-        obj->dev->TFI3 = buf[0] & 0xC00F0000;
-        obj->dev->TID3 = buf[1];
-        obj->dev->TDA3 = buf[2];
-        obj->dev->TDB3 = buf[3];
-        if (cc) {
-            obj->dev->CMR = 0x90;
-        } else {
-            obj->dev->CMR = 0x81;
-        }
-        return 1;
-    }
-
-    return 0;
-}
-
-int can_read(can_t *obj, CAN_Message *msg) {
-    CANMsg x;
-    unsigned int *i = (unsigned int *)&x;
-
-    can_enable(obj);
-
-    if (obj->dev->GSR & 0x1) {
-        *i++ = obj->dev->RFS;  // Frame
-        *i++ = obj->dev->RID;  // ID
-        *i++ = obj->dev->RDA;  // Data A
-        *i++ = obj->dev->RDB;  // Data B
-        obj->dev->CMR = 0x04;  // release receive buffer
-
-        msg->id     = x.id;
-        msg->len    = x.dlc;
-        msg->format = (x.type)? CANExtended : CANStandard;
-        msg->type   = (x.rtr)?  CANRemote:    CANData;
-        memcpy(msg->data,x.data,x.dlc);
-        return 1;
-    }
-
-    return 0;
-}
-
-void can_reset(can_t *obj) {
-    can_disable(obj);
-    obj->dev->GSR = 0; // Reset error counter when CAN1MOD is in reset
-}
-
-unsigned char can_rderror(can_t *obj) {
-    return (obj->dev->GSR >> 16) & 0xFF;
-}
-
-unsigned char can_tderror(can_t *obj) {
-    return (obj->dev->GSR >> 24) & 0xFF;
-}
-
-void can_monitor(can_t *obj, int silent) {
-    uint32_t mod_mask = can_disable(obj);
-    if (silent) {
-        obj->dev->MOD |= (1 << 1);
-    } else {
-        obj->dev->MOD &= ~(1 << 1);
-    }
-    if (!(mod_mask & 1)) {
-        can_enable(obj);
-    }
-}