Tomo Yamanaka / mbed-dev

mbed library sources. Supersedes mbed-src. GR-PEACH runs on RAM.

Fork of mbed-dev by mbed official

targets/hal/TARGET_NXP/TARGET_LPC23XX/can_api.c@103:493a29d2d4d7, 2016-03-30 (annotated)

Committer:
1050186
Date:
Wed Mar 30 11:41:25 2016 +0000
Revision:
103:493a29d2d4d7
Parent:
0:9b334a45a8ff 
GR-PEACH runs on RAM.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 0:9b334a45a8ff 1 /* mbed Microcontroller Library
bogdanm 0:9b334a45a8ff 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 0:9b334a45a8ff 3 *
bogdanm 0:9b334a45a8ff 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 0:9b334a45a8ff 5 * you may not use this file except in compliance with the License.
bogdanm 0:9b334a45a8ff 6 * You may obtain a copy of the License at
bogdanm 0:9b334a45a8ff 7 *
bogdanm 0:9b334a45a8ff 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 0:9b334a45a8ff 9 *
bogdanm 0:9b334a45a8ff 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 0:9b334a45a8ff 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 0:9b334a45a8ff 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 0:9b334a45a8ff 13 * See the License for the specific language governing permissions and
bogdanm 0:9b334a45a8ff 14 * limitations under the License.
bogdanm 0:9b334a45a8ff 15 */
bogdanm 0:9b334a45a8ff 16 #include "mbed_assert.h"
bogdanm 0:9b334a45a8ff 17 #include "can_api.h"
bogdanm 0:9b334a45a8ff 18 #include "cmsis.h"
bogdanm 0:9b334a45a8ff 19 #include "pinmap.h"
bogdanm 0:9b334a45a8ff 20
bogdanm 0:9b334a45a8ff 21 #include <math.h>
bogdanm 0:9b334a45a8ff 22 #include <string.h>
bogdanm 0:9b334a45a8ff 23
bogdanm 0:9b334a45a8ff 24 /* Acceptance filter mode in AFMR register */
bogdanm 0:9b334a45a8ff 25 #define ACCF_OFF 0x01
bogdanm 0:9b334a45a8ff 26 #define ACCF_BYPASS 0x02
bogdanm 0:9b334a45a8ff 27 #define ACCF_ON 0x00
bogdanm 0:9b334a45a8ff 28 #define ACCF_FULLCAN 0x04
bogdanm 0:9b334a45a8ff 29
bogdanm 0:9b334a45a8ff 30 /* There are several bit timing calculators on the internet.
bogdanm 0:9b334a45a8ff 31 http://www.port.de/engl/canprod/sv_req_form.html
bogdanm 0:9b334a45a8ff 32 http://www.kvaser.com/can/index.htm
bogdanm 0:9b334a45a8ff 33 */
bogdanm 0:9b334a45a8ff 34
bogdanm 0:9b334a45a8ff 35 static const PinMap PinMap_CAN_RD[] = {
bogdanm 0:9b334a45a8ff 36 {P0_0 , CAN_1, 1},
bogdanm 0:9b334a45a8ff 37 {P0_4 , CAN_2, 2},
bogdanm 0:9b334a45a8ff 38 {P0_21, CAN_1, 3},
bogdanm 0:9b334a45a8ff 39 {P2_7 , CAN_2, 1},
bogdanm 0:9b334a45a8ff 40 {NC , NC , 0}
bogdanm 0:9b334a45a8ff 41 };
bogdanm 0:9b334a45a8ff 42
bogdanm 0:9b334a45a8ff 43 static const PinMap PinMap_CAN_TD[] = {
bogdanm 0:9b334a45a8ff 44 {P0_1 , CAN_1, 1},
bogdanm 0:9b334a45a8ff 45 {P0_5 , CAN_2, 2},
bogdanm 0:9b334a45a8ff 46 {P0_22, CAN_1, 3},
bogdanm 0:9b334a45a8ff 47 {P2_8 , CAN_2, 1},
bogdanm 0:9b334a45a8ff 48 {NC , NC , 0}
bogdanm 0:9b334a45a8ff 49 };
bogdanm 0:9b334a45a8ff 50
bogdanm 0:9b334a45a8ff 51 // Type definition to hold a CAN message
bogdanm 0:9b334a45a8ff 52 struct CANMsg {
bogdanm 0:9b334a45a8ff 53 unsigned int reserved1 : 16;
bogdanm 0:9b334a45a8ff 54 unsigned int dlc : 4; // Bits 16..19: DLC - Data Length Counter
bogdanm 0:9b334a45a8ff 55 unsigned int reserved0 : 10;
bogdanm 0:9b334a45a8ff 56 unsigned int rtr : 1; // Bit 30: Set if this is a RTR message
bogdanm 0:9b334a45a8ff 57 unsigned int type : 1; // Bit 31: Set if this is a 29-bit ID message
bogdanm 0:9b334a45a8ff 58 unsigned int id; // CAN Message ID (11-bit or 29-bit)
bogdanm 0:9b334a45a8ff 59 unsigned char data[8]; // CAN Message Data Bytes 0-7
bogdanm 0:9b334a45a8ff 60 };
bogdanm 0:9b334a45a8ff 61 typedef struct CANMsg CANMsg;
bogdanm 0:9b334a45a8ff 62
bogdanm 0:9b334a45a8ff 63 static uint32_t can_disable(can_t *obj) {
bogdanm 0:9b334a45a8ff 64 uint32_t sm = obj->dev->MOD;
bogdanm 0:9b334a45a8ff 65 obj->dev->MOD |= 1;
bogdanm 0:9b334a45a8ff 66 return sm;
bogdanm 0:9b334a45a8ff 67 }
bogdanm 0:9b334a45a8ff 68
bogdanm 0:9b334a45a8ff 69 static inline void can_enable(can_t *obj) {
bogdanm 0:9b334a45a8ff 70 if (obj->dev->MOD & 1) {
bogdanm 0:9b334a45a8ff 71 obj->dev->MOD &= ~(1);
bogdanm 0:9b334a45a8ff 72 }
bogdanm 0:9b334a45a8ff 73 }
bogdanm 0:9b334a45a8ff 74
bogdanm 0:9b334a45a8ff 75 int can_mode(can_t *obj, CanMode mode) {
bogdanm 0:9b334a45a8ff 76 return 0; // not implemented
bogdanm 0:9b334a45a8ff 77 }
bogdanm 0:9b334a45a8ff 78
bogdanm 0:9b334a45a8ff 79 int can_filter(can_t *obj, uint32_t id, uint32_t mask, CANFormat format, int32_t handle) {
bogdanm 0:9b334a45a8ff 80 return 0; // not implemented
bogdanm 0:9b334a45a8ff 81 }
bogdanm 0:9b334a45a8ff 82
bogdanm 0:9b334a45a8ff 83 static int can_pclk(can_t *obj) {
bogdanm 0:9b334a45a8ff 84 int value = 0;
bogdanm 0:9b334a45a8ff 85 switch ((int)obj->dev) {
bogdanm 0:9b334a45a8ff 86 case CAN_1: value = (LPC_SC->PCLKSEL0 & (0x3 << 26)) >> 26; break;
bogdanm 0:9b334a45a8ff 87 case CAN_2: value = (LPC_SC->PCLKSEL0 & (0x3 << 28)) >> 28; break;
bogdanm 0:9b334a45a8ff 88 }
bogdanm 0:9b334a45a8ff 89
bogdanm 0:9b334a45a8ff 90 switch (value) {
bogdanm 0:9b334a45a8ff 91 case 1: return 1;
bogdanm 0:9b334a45a8ff 92 case 2: return 2;
bogdanm 0:9b334a45a8ff 93 case 3: return 6;
bogdanm 0:9b334a45a8ff 94 default: return 4;
bogdanm 0:9b334a45a8ff 95 }
bogdanm 0:9b334a45a8ff 96 }
bogdanm 0:9b334a45a8ff 97
bogdanm 0:9b334a45a8ff 98 // This table has the sampling points as close to 75% as possible. The first
bogdanm 0:9b334a45a8ff 99 // value is TSEG1, the second TSEG2.
bogdanm 0:9b334a45a8ff 100 static const int timing_pts[23][2] = {
bogdanm 0:9b334a45a8ff 101 {0x0, 0x0}, // 2, 50%
bogdanm 0:9b334a45a8ff 102 {0x1, 0x0}, // 3, 67%
bogdanm 0:9b334a45a8ff 103 {0x2, 0x0}, // 4, 75%
bogdanm 0:9b334a45a8ff 104 {0x3, 0x0}, // 5, 80%
bogdanm 0:9b334a45a8ff 105 {0x3, 0x1}, // 6, 67%
bogdanm 0:9b334a45a8ff 106 {0x4, 0x1}, // 7, 71%
bogdanm 0:9b334a45a8ff 107 {0x5, 0x1}, // 8, 75%
bogdanm 0:9b334a45a8ff 108 {0x6, 0x1}, // 9, 78%
bogdanm 0:9b334a45a8ff 109 {0x6, 0x2}, // 10, 70%
bogdanm 0:9b334a45a8ff 110 {0x7, 0x2}, // 11, 73%
bogdanm 0:9b334a45a8ff 111 {0x8, 0x2}, // 12, 75%
bogdanm 0:9b334a45a8ff 112 {0x9, 0x2}, // 13, 77%
bogdanm 0:9b334a45a8ff 113 {0x9, 0x3}, // 14, 71%
bogdanm 0:9b334a45a8ff 114 {0xA, 0x3}, // 15, 73%
bogdanm 0:9b334a45a8ff 115 {0xB, 0x3}, // 16, 75%
bogdanm 0:9b334a45a8ff 116 {0xC, 0x3}, // 17, 76%
bogdanm 0:9b334a45a8ff 117 {0xD, 0x3}, // 18, 78%
bogdanm 0:9b334a45a8ff 118 {0xD, 0x4}, // 19, 74%
bogdanm 0:9b334a45a8ff 119 {0xE, 0x4}, // 20, 75%
bogdanm 0:9b334a45a8ff 120 {0xF, 0x4}, // 21, 76%
bogdanm 0:9b334a45a8ff 121 {0xF, 0x5}, // 22, 73%
bogdanm 0:9b334a45a8ff 122 {0xF, 0x6}, // 23, 70%
bogdanm 0:9b334a45a8ff 123 {0xF, 0x7}, // 24, 67%
bogdanm 0:9b334a45a8ff 124 };
bogdanm 0:9b334a45a8ff 125
bogdanm 0:9b334a45a8ff 126 static unsigned int can_speed(unsigned int sclk, unsigned int pclk, unsigned int cclk, unsigned char psjw) {
bogdanm 0:9b334a45a8ff 127 uint32_t btr;
bogdanm 0:9b334a45a8ff 128 uint16_t brp = 0;
bogdanm 0:9b334a45a8ff 129 uint32_t calcbit;
bogdanm 0:9b334a45a8ff 130 uint32_t bitwidth;
bogdanm 0:9b334a45a8ff 131 int hit = 0;
bogdanm 0:9b334a45a8ff 132 int bits;
bogdanm 0:9b334a45a8ff 133
bogdanm 0:9b334a45a8ff 134 bitwidth = sclk / (pclk * cclk);
bogdanm 0:9b334a45a8ff 135
bogdanm 0:9b334a45a8ff 136 brp = bitwidth / 0x18;
bogdanm 0:9b334a45a8ff 137 while ((!hit) && (brp < bitwidth / 4)) {
bogdanm 0:9b334a45a8ff 138 brp++;
bogdanm 0:9b334a45a8ff 139 for (bits = 22; bits > 0; bits--) {
bogdanm 0:9b334a45a8ff 140 calcbit = (bits + 3) * (brp + 1);
bogdanm 0:9b334a45a8ff 141 if (calcbit == bitwidth) {
bogdanm 0:9b334a45a8ff 142 hit = 1;
bogdanm 0:9b334a45a8ff 143 break;
bogdanm 0:9b334a45a8ff 144 }
bogdanm 0:9b334a45a8ff 145 }
bogdanm 0:9b334a45a8ff 146 }
bogdanm 0:9b334a45a8ff 147
bogdanm 0:9b334a45a8ff 148 if (hit) {
bogdanm 0:9b334a45a8ff 149 btr = ((timing_pts[bits][1] << 20) & 0x00700000)
bogdanm 0:9b334a45a8ff 150 | ((timing_pts[bits][0] << 16) & 0x000F0000)
bogdanm 0:9b334a45a8ff 151 | ((psjw << 14) & 0x0000C000)
bogdanm 0:9b334a45a8ff 152 | ((brp << 0) & 0x000003FF);
bogdanm 0:9b334a45a8ff 153 } else {
bogdanm 0:9b334a45a8ff 154 btr = 0xFFFFFFFF;
bogdanm 0:9b334a45a8ff 155 }
bogdanm 0:9b334a45a8ff 156
bogdanm 0:9b334a45a8ff 157 return btr;
bogdanm 0:9b334a45a8ff 158 }
bogdanm 0:9b334a45a8ff 159
bogdanm 0:9b334a45a8ff 160 void can_init(can_t *obj, PinName rd, PinName td) {
bogdanm 0:9b334a45a8ff 161 CANName can_rd = (CANName)pinmap_peripheral(rd, PinMap_CAN_RD);
bogdanm 0:9b334a45a8ff 162 CANName can_td = (CANName)pinmap_peripheral(td, PinMap_CAN_TD);
bogdanm 0:9b334a45a8ff 163 obj->dev = (LPC_CAN_TypeDef *)pinmap_merge(can_rd, can_td);
bogdanm 0:9b334a45a8ff 164 MBED_ASSERT((int)obj->dev != NC);
bogdanm 0:9b334a45a8ff 165
bogdanm 0:9b334a45a8ff 166 switch ((int)obj->dev) {
bogdanm 0:9b334a45a8ff 167 case CAN_1: LPC_SC->PCONP |= 1 << 13; break;
bogdanm 0:9b334a45a8ff 168 case CAN_2: LPC_SC->PCONP |= 1 << 14; break;
bogdanm 0:9b334a45a8ff 169 }
bogdanm 0:9b334a45a8ff 170
bogdanm 0:9b334a45a8ff 171 pinmap_pinout(rd, PinMap_CAN_RD);
bogdanm 0:9b334a45a8ff 172 pinmap_pinout(td, PinMap_CAN_TD);
bogdanm 0:9b334a45a8ff 173
bogdanm 0:9b334a45a8ff 174 can_reset(obj);
bogdanm 0:9b334a45a8ff 175 obj->dev->IER = 0; // Disable Interrupts
bogdanm 0:9b334a45a8ff 176 can_frequency(obj, 100000);
bogdanm 0:9b334a45a8ff 177
bogdanm 0:9b334a45a8ff 178 LPC_CANAF->AFMR = ACCF_BYPASS; // Bypass Filter
bogdanm 0:9b334a45a8ff 179 }
bogdanm 0:9b334a45a8ff 180
bogdanm 0:9b334a45a8ff 181 void can_free(can_t *obj) {
bogdanm 0:9b334a45a8ff 182 switch ((int)obj->dev) {
bogdanm 0:9b334a45a8ff 183 case CAN_1: LPC_SC->PCONP &= ~(1 << 13); break;
bogdanm 0:9b334a45a8ff 184 case CAN_2: LPC_SC->PCONP &= ~(1 << 14); break;
bogdanm 0:9b334a45a8ff 185 }
bogdanm 0:9b334a45a8ff 186 }
bogdanm 0:9b334a45a8ff 187
bogdanm 0:9b334a45a8ff 188 int can_frequency(can_t *obj, int f) {
bogdanm 0:9b334a45a8ff 189 int pclk = can_pclk(obj);
bogdanm 0:9b334a45a8ff 190 int btr = can_speed(SystemCoreClock, pclk, (unsigned int)f, 1);
bogdanm 0:9b334a45a8ff 191
bogdanm 0:9b334a45a8ff 192 if (btr > 0) {
bogdanm 0:9b334a45a8ff 193 uint32_t modmask = can_disable(obj);
bogdanm 0:9b334a45a8ff 194 obj->dev->BTR = btr;
bogdanm 0:9b334a45a8ff 195 obj->dev->MOD = modmask;
bogdanm 0:9b334a45a8ff 196 return 1;
bogdanm 0:9b334a45a8ff 197 } else {
bogdanm 0:9b334a45a8ff 198 return 0;
bogdanm 0:9b334a45a8ff 199 }
bogdanm 0:9b334a45a8ff 200 }
bogdanm 0:9b334a45a8ff 201
bogdanm 0:9b334a45a8ff 202 int can_write(can_t *obj, CAN_Message msg, int cc) {
bogdanm 0:9b334a45a8ff 203 unsigned int CANStatus;
bogdanm 0:9b334a45a8ff 204 CANMsg m;
bogdanm 0:9b334a45a8ff 205
bogdanm 0:9b334a45a8ff 206 can_enable(obj);
bogdanm 0:9b334a45a8ff 207
bogdanm 0:9b334a45a8ff 208 m.id = msg.id ;
bogdanm 0:9b334a45a8ff 209 m.dlc = msg.len & 0xF;
bogdanm 0:9b334a45a8ff 210 m.rtr = msg.type;
bogdanm 0:9b334a45a8ff 211 m.type = msg.format;
bogdanm 0:9b334a45a8ff 212 memcpy(m.data, msg.data, msg.len);
bogdanm 0:9b334a45a8ff 213 const unsigned int *buf = (const unsigned int *)&m;
bogdanm 0:9b334a45a8ff 214
bogdanm 0:9b334a45a8ff 215 CANStatus = obj->dev->SR;
bogdanm 0:9b334a45a8ff 216 if (CANStatus & 0x00000004) {
bogdanm 0:9b334a45a8ff 217 obj->dev->TFI1 = buf[0] & 0xC00F0000;
bogdanm 0:9b334a45a8ff 218 obj->dev->TID1 = buf[1];
bogdanm 0:9b334a45a8ff 219 obj->dev->TDA1 = buf[2];
bogdanm 0:9b334a45a8ff 220 obj->dev->TDB1 = buf[3];
bogdanm 0:9b334a45a8ff 221 if (cc) {
bogdanm 0:9b334a45a8ff 222 obj->dev->CMR = 0x30;
bogdanm 0:9b334a45a8ff 223 } else {
bogdanm 0:9b334a45a8ff 224 obj->dev->CMR = 0x21;
bogdanm 0:9b334a45a8ff 225 }
bogdanm 0:9b334a45a8ff 226 return 1;
bogdanm 0:9b334a45a8ff 227
bogdanm 0:9b334a45a8ff 228 } else if (CANStatus & 0x00000400) {
bogdanm 0:9b334a45a8ff 229 obj->dev->TFI2 = buf[0] & 0xC00F0000;
bogdanm 0:9b334a45a8ff 230 obj->dev->TID2 = buf[1];
bogdanm 0:9b334a45a8ff 231 obj->dev->TDA2 = buf[2];
bogdanm 0:9b334a45a8ff 232 obj->dev->TDB2 = buf[3];
bogdanm 0:9b334a45a8ff 233 if (cc) {
bogdanm 0:9b334a45a8ff 234 obj->dev->CMR = 0x50;
bogdanm 0:9b334a45a8ff 235 } else {
bogdanm 0:9b334a45a8ff 236 obj->dev->CMR = 0x41;
bogdanm 0:9b334a45a8ff 237 }
bogdanm 0:9b334a45a8ff 238 return 1;
bogdanm 0:9b334a45a8ff 239
bogdanm 0:9b334a45a8ff 240 } else if (CANStatus & 0x00040000) {
bogdanm 0:9b334a45a8ff 241 obj->dev->TFI3 = buf[0] & 0xC00F0000;
bogdanm 0:9b334a45a8ff 242 obj->dev->TID3 = buf[1];
bogdanm 0:9b334a45a8ff 243 obj->dev->TDA3 = buf[2];
bogdanm 0:9b334a45a8ff 244 obj->dev->TDB3 = buf[3];
bogdanm 0:9b334a45a8ff 245 if (cc) {
bogdanm 0:9b334a45a8ff 246 obj->dev->CMR = 0x90;
bogdanm 0:9b334a45a8ff 247 } else {
bogdanm 0:9b334a45a8ff 248 obj->dev->CMR = 0x81;
bogdanm 0:9b334a45a8ff 249 }
bogdanm 0:9b334a45a8ff 250 return 1;
bogdanm 0:9b334a45a8ff 251 }
bogdanm 0:9b334a45a8ff 252
bogdanm 0:9b334a45a8ff 253 return 0;
bogdanm 0:9b334a45a8ff 254 }
bogdanm 0:9b334a45a8ff 255
bogdanm 0:9b334a45a8ff 256 int can_read(can_t *obj, CAN_Message *msg, int handle) {
bogdanm 0:9b334a45a8ff 257 CANMsg x;
bogdanm 0:9b334a45a8ff 258 unsigned int *i = (unsigned int *)&x;
bogdanm 0:9b334a45a8ff 259
bogdanm 0:9b334a45a8ff 260 can_enable(obj);
bogdanm 0:9b334a45a8ff 261
bogdanm 0:9b334a45a8ff 262 if (obj->dev->GSR & 0x1) {
bogdanm 0:9b334a45a8ff 263 *i++ = obj->dev->RFS; // Frame
bogdanm 0:9b334a45a8ff 264 *i++ = obj->dev->RID; // ID
bogdanm 0:9b334a45a8ff 265 *i++ = obj->dev->RDA; // Data A
bogdanm 0:9b334a45a8ff 266 *i++ = obj->dev->RDB; // Data B
bogdanm 0:9b334a45a8ff 267 obj->dev->CMR = 0x04; // release receive buffer
bogdanm 0:9b334a45a8ff 268
bogdanm 0:9b334a45a8ff 269 msg->id = x.id;
bogdanm 0:9b334a45a8ff 270 msg->len = x.dlc;
bogdanm 0:9b334a45a8ff 271 msg->format = (x.type)? CANExtended : CANStandard;
bogdanm 0:9b334a45a8ff 272 msg->type = (x.rtr)? CANRemote: CANData;
bogdanm 0:9b334a45a8ff 273 memcpy(msg->data,x.data,x.dlc);
bogdanm 0:9b334a45a8ff 274 return 1;
bogdanm 0:9b334a45a8ff 275 }
bogdanm 0:9b334a45a8ff 276
bogdanm 0:9b334a45a8ff 277 return 0;
bogdanm 0:9b334a45a8ff 278 }
bogdanm 0:9b334a45a8ff 279
bogdanm 0:9b334a45a8ff 280 void can_reset(can_t *obj) {
bogdanm 0:9b334a45a8ff 281 can_disable(obj);
bogdanm 0:9b334a45a8ff 282 obj->dev->GSR = 0; // Reset error counter when CAN1MOD is in reset
bogdanm 0:9b334a45a8ff 283 }
bogdanm 0:9b334a45a8ff 284
bogdanm 0:9b334a45a8ff 285 unsigned char can_rderror(can_t *obj) {
bogdanm 0:9b334a45a8ff 286 return (obj->dev->GSR >> 16) & 0xFF;
bogdanm 0:9b334a45a8ff 287 }
bogdanm 0:9b334a45a8ff 288
bogdanm 0:9b334a45a8ff 289 unsigned char can_tderror(can_t *obj) {
bogdanm 0:9b334a45a8ff 290 return (obj->dev->GSR >> 24) & 0xFF;
bogdanm 0:9b334a45a8ff 291 }
bogdanm 0:9b334a45a8ff 292
bogdanm 0:9b334a45a8ff 293 void can_monitor(can_t *obj, int silent) {
bogdanm 0:9b334a45a8ff 294 uint32_t mod_mask = can_disable(obj);
bogdanm 0:9b334a45a8ff 295 if (silent) {
bogdanm 0:9b334a45a8ff 296 obj->dev->MOD |= (1 << 1);
bogdanm 0:9b334a45a8ff 297 } else {
bogdanm 0:9b334a45a8ff 298 obj->dev->MOD &= ~(1 << 1);
bogdanm 0:9b334a45a8ff 299 }
bogdanm 0:9b334a45a8ff 300 if (!(mod_mask & 1)) {
bogdanm 0:9b334a45a8ff 301 can_enable(obj);
bogdanm 0:9b334a45a8ff 302 }
bogdanm 0:9b334a45a8ff 303 }