mbed library sources
Dependents: frdm_kl05z_gpio_test
Fork of mbed-src by
targets/hal/TARGET_NXP/TARGET_LPC11XX_11CXX/TARGET_LPC11CXX/can_api.c
- Committer:
- mbed_official
- Date:
- 2014-07-08
- Revision:
- 251:de9a1e4ffd79
- Parent:
- 250:a49055e7a707
- Child:
- 285:31249416b6f9
File content as of revision 251:de9a1e4ffd79:
/* 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 "error.h" #include <math.h> #include <string.h> /* Handy defines */ #define MSG_OBJ_MAX 32 #define DLC_MAX 8 #define ID_STD_MASK 0x07FF #define ID_EXT_MASK 0x1FFFFFFF #define DLC_MASK 0x0F static uint32_t can_irq_id = 0; static can_irq_handler irq_handler; static uint32_t can_disable(can_t *obj) { uint32_t sm = LPC_CAN->CNTL; LPC_CAN->CNTL |= CANCNTL_INIT; return sm; } static inline void can_enable(can_t *obj) { if (LPC_CAN->CNTL & CANCNTL_INIT) { LPC_CAN->CNTL &= ~CANCNTL_INIT; } } int can_mode(can_t *obj, CanMode mode) { return 0; // not implemented } int can_filter(can_t *obj, uint32_t id, uint32_t mask, CANFormat format, int32_t handle) { uint16_t i; // Find first free message object if(handle == 0) { uint32_t msgval = LPC_CAN->MSGV1 | (LPC_CAN->MSGV2 << 16); // Find first free messagebox for(i = 0; i < 32; i++) { if((msgval & (1 << i)) == 0) { handle = i+1; break; } } } if(handle > 0 && handle < 32) { if(format == CANExtended) { // Mark message valid, Direction = TX, Extended Frame, Set Identifier and mask everything LPC_CAN->IF1_ARB1 = BFN_PREP(id, CANIFn_ARB1_ID); LPC_CAN->IF1_ARB2 = CANIFn_ARB2_MSGVAL | CANIFn_ARB2_XTD | BFN_PREP(id >> 16, CANIFn_ARB2_ID); LPC_CAN->IF1_MSK1 = BFN_PREP(mask, CANIFn_MSK1_MSK); LPC_CAN->IF1_MSK2 = CANIFn_MSK2_MXTD /* | CANIFn_MSK2_MDIR */ | BFN_PREP(mask >> 16, CANIFn_MSK2_MSK); } else { // Mark message valid, Direction = TX, Set Identifier and mask everything LPC_CAN->IF1_ARB2 = CANIFn_ARB2_MSGVAL | BFN_PREP(id << 2, CANIFn_ARB2_ID); LPC_CAN->IF1_MSK2 = /* CANIFn_MSK2_MDIR | */ BFN_PREP(mask << 2, CANIFn_MSK2_MSK); } // Use mask, single message object and set DLC LPC_CAN->IF1_MCTRL = CANIFn_MCTRL_UMASK | CANIFn_MCTRL_EOB | CANIFn_MCTRL_RXIE | BFN_PREP(DLC_MAX, CANIFn_MCTRL_DLC); // Transfer all fields to message object LPC_CAN->IF1_CMDMSK = CANIFn_CMDMSK_WR | CANIFn_CMDMSK_MASK | CANIFn_CMDMSK_ARB | CANIFn_CMDMSK_CTRL; // Start Transfer to given message number LPC_CAN->IF1_CMDREQ = BFN_PREP(handle, CANIFn_CMDREQ_MN); // Wait until transfer to message ram complete - TODO: maybe not block?? while( LPC_CAN->IF1_CMDREQ & CANIFn_CMDREQ_BUSY ); } return handle; } static inline void can_irq() { irq_handler(can_irq_id, IRQ_RX); } // Register CAN object's irq handler void can_irq_init(can_t *obj, can_irq_handler handler, uint32_t id) { irq_handler = handler; can_irq_id = id; } // Unregister CAN object's irq handler void can_irq_free(can_t *obj) { LPC_CAN->CNTL &= ~CANCNTL_IE; // Disable Interrupts :) can_irq_id = 0; NVIC_DisableIRQ(CAN_IRQn); } // Clear or set a irq void can_irq_set(can_t *obj, CanIrqType type, uint32_t enable) { // Put CAN in Reset Mode and enable interrupt can_disable(obj); if(enable == 0) { LPC_CAN->CNTL &= ~(CANCNTL_IE | CANCNTL_SIE); } else { LPC_CAN->CNTL |= CANCNTL_IE | CANCNTL_SIE; } // Take it out of reset... can_enable(obj); // Enable NVIC if at least 1 interrupt is active NVIC_SetVector(CAN_IRQn, (uint32_t) &can_irq); NVIC_EnableIRQ(CAN_IRQn); } // 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 cclk, unsigned char psjw) { uint32_t btr; uint32_t clkdiv = 1; uint16_t brp = 0; uint32_t calcbit; uint32_t bitwidth; int hit = 0; int bits = 0; bitwidth = sclk / 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; } } } /* This might be funky while(btr > 63 && clkdiv < 16) { btr = btr / 2; clkdiv = clkdiv * 2; } */ clkdiv = clkdiv - 1; if (hit) { btr = BFN_PREP(timing_pts[bits][1], CANBT_TSEG2) | BFN_PREP(timing_pts[bits][0], CANBT_TSEG1) | BFN_PREP(psjw, CANBT_SJW) | BFN_PREP(brp, CANBT_BRP); btr = btr | (clkdiv << 16); } else { btr = 0; } return btr; } int can_config_rxmsgobj(can_t *obj) { uint16_t i = 0; // Make sure the interface is available //while( LPC_CAN->IF1_CMDREQ & CANIFn_CMDREQ_BUSY ); // Mark message valid, Direction = RX, Don't care about anything else LPC_CAN->IF1_ARB1 = 0; LPC_CAN->IF1_ARB2 = 0; LPC_CAN->IF1_MCTRL = 0; for ( i = 0; i < MSG_OBJ_MAX; i++ ) { // Transfer arb and control fields to message object LPC_CAN->IF1_CMDMSK = CANIFn_CMDMSK_WR | CANIFn_CMDMSK_ARB | CANIFn_CMDMSK_CTRL | CANIFn_CMDMSK_TXRQST; // Start Transfer to given message number LPC_CAN->IF1_CMDREQ = BFN_PREP(i, CANIFn_CMDREQ_MN); // Wait until transfer to message ram complete - TODO: maybe not block?? while( LPC_CAN->IF1_CMDREQ & CANIFn_CMDREQ_BUSY ); } // Accept all messages can_filter(obj, 0, 0, CANStandard, 1); return 1; } void can_init(can_t *obj, PinName rd, PinName td) { // Enable power and clock LPC_SYSCON->PRESETCTRL |= PRESETCTRL_CAN_RST_N; LPC_SYSCON->SYSAHBCLKCTRL |= SYSAHBCLKCTRL_CAN; // Enable Initialization mode if (!(LPC_CAN->CNTL & CANCNTL_INIT)) { LPC_CAN->CNTL |= CANCNTL_INIT; } can_frequency(obj, 125000); // Resume operation LPC_CAN->CNTL &= ~CANCNTL_INIT; while ( LPC_CAN->CNTL & CANCNTL_INIT ); // Initialize RX message object can_config_rxmsgobj(obj); } void can_free(can_t *obj) { LPC_SYSCON->SYSAHBCLKCTRL &= ~(SYSAHBCLKCTRL_CAN); LPC_SYSCON->PRESETCTRL &= ~(PRESETCTRL_CAN_RST_N); } int can_frequency(can_t *obj, int f) { int btr = can_speed(SystemCoreClock, (unsigned int)f, 1); int clkdiv = (btr >> 16) & 0x0F; btr = btr & 0xFFFF; if (btr > 0) { uint32_t cntl_init = LPC_CAN->CNTL | CANCNTL_INIT; // Set the bit clock LPC_CAN->CNTL |= CANCNTL_CCE | CANCNTL_INIT; LPC_CAN->CLKDIV = clkdiv; LPC_CAN->BT = btr; LPC_CAN->BRPE = 0x0000; LPC_CAN->CNTL &= ~(CANCNTL_CCE | CANCNTL_INIT); LPC_CAN->CNTL |= cntl_init; return 1; } return 0; } int can_write(can_t *obj, CAN_Message msg, int cc) { uint16_t msgnum = 0; // Make sure controller is enabled can_enable(obj); // Make sure the interface is available while( LPC_CAN->IF1_CMDREQ & CANIFn_CMDREQ_BUSY ); // Set the direction bit based on the message type uint32_t direction = 0; if (msg.type == CANData) { direction = CANIFn_ARB2_DIR; } if(msg.format == CANExtended) { // Mark message valid, Extended Frame, Set Identifier and mask everything LPC_CAN->IF1_ARB1 = BFN_PREP(msg.id, CANIFn_ARB1_ID); LPC_CAN->IF1_ARB2 = CANIFn_ARB2_MSGVAL | CANIFn_ARB2_XTD | direction | BFN_PREP(msg.id >> 16, CANIFn_ARB2_ID); LPC_CAN->IF1_MSK1 = BFN_PREP(ID_EXT_MASK, CANIFn_MSK1_MSK); LPC_CAN->IF1_MSK2 = CANIFn_MSK2_MXTD | CANIFn_MSK2_MDIR | BFN_PREP(ID_EXT_MASK >> 16, CANIFn_MSK2_MSK); } else { // Mark message valid, Set Identifier and mask everything LPC_CAN->IF1_ARB2 = CANIFn_ARB2_MSGVAL | direction | BFN_PREP(msg.id << 2, CANIFn_ARB2_ID); LPC_CAN->IF1_MSK2 = CANIFn_MSK2_MDIR | BFN_PREP(ID_STD_MASK << 2, CANIFn_MSK2_MSK); } // Use mask, request transmission, single message object and set DLC LPC_CAN->IF1_MCTRL = CANIFn_MCTRL_UMASK | CANIFn_MCTRL_TXRQST | CANIFn_MCTRL_EOB | BFN_PREP(msg.len, CANIFn_MCTRL_DLC); LPC_CAN->IF1_DA1 = BFN_PREP(msg.data[1], CANIFn_DA1_DATA1) | BFN_PREP(msg.data[0], CANIFn_DA1_DATA0); LPC_CAN->IF1_DA2 = BFN_PREP(msg.data[3], CANIFn_DA2_DATA3) | BFN_PREP(msg.data[2], CANIFn_DA2_DATA2); LPC_CAN->IF1_DB1 = BFN_PREP(msg.data[5], CANIFn_DB1_DATA5) | BFN_PREP(msg.data[4], CANIFn_DB1_DATA4); LPC_CAN->IF1_DB2 = BFN_PREP(msg.data[7], CANIFn_DB2_DATA7) | BFN_PREP(msg.data[6], CANIFn_DB2_DATA6); // Transfer all fields to message object LPC_CAN->IF1_CMDMSK = CANIFn_CMDMSK_WR | CANIFn_CMDMSK_MASK | CANIFn_CMDMSK_ARB | CANIFn_CMDMSK_CTRL | CANIFn_CMDMSK_TXRQST | CANIFn_CMDMSK_DATA_A | CANIFn_CMDMSK_DATA_B; // Start Transfer to given message number LPC_CAN->IF1_CMDREQ = BFN_PREP(msgnum, CANIFn_CMDREQ_MN); // Wait until transfer to message ram complete - TODO: maybe not block?? while( LPC_CAN->IF1_CMDREQ & CANIFn_CMDREQ_BUSY); // Wait until TXOK is set, then clear it - TODO: maybe not block //while( !(LPC_CAN->STAT & CANSTAT_TXOK) ); LPC_CAN->STAT &= ~(CANSTAT_TXOK); return 1; } int can_read(can_t *obj, CAN_Message *msg, int handle) { uint16_t i; // Make sure controller is enabled can_enable(obj); // Find first message object with new data if(handle == 0) { uint32_t newdata = LPC_CAN->ND1 | (LPC_CAN->ND2 << 16); // Find first free messagebox for(i = 0; i < 32; i++) { if(newdata & (1 << i)) { handle = i+1; break; } } } if(handle > 0 && handle < 32) { // Wait until message interface is free while( LPC_CAN->IF2_CMDREQ & CANIFn_CMDREQ_BUSY ); // Transfer all fields to message object LPC_CAN->IF2_CMDMSK = CANIFn_CMDMSK_RD | CANIFn_CMDMSK_MASK | CANIFn_CMDMSK_ARB | CANIFn_CMDMSK_CTRL | CANIFn_CMDMSK_CLRINTPND | CANIFn_CMDMSK_TXRQST | CANIFn_CMDMSK_DATA_A | CANIFn_CMDMSK_DATA_B; // Start Transfer from given message number LPC_CAN->IF2_CMDREQ = BFN_PREP(handle, CANIFn_CMDREQ_MN); // Wait until transfer to message ram complete while( LPC_CAN->IF2_CMDREQ & CANIFn_CMDREQ_BUSY ); if (LPC_CAN->IF2_ARB2 & CANIFn_ARB2_XTD) { msg->format = CANExtended; msg->id = (LPC_CAN->IF2_ARB1 & CANIFn_ARB2_ID_MASK) << 16; msg->id |= (LPC_CAN->IF2_ARB2 & CANIFn_ARB2_ID_MASK); } else { msg->format = CANStandard; msg->id = (LPC_CAN->IF2_ARB2 & CANIFn_ARB2_ID_MASK) >> 2; } if (LPC_CAN->IF2_ARB2 & CANIFn_ARB2_DIR) { msg->type = CANRemote; } else { msg->type = CANData; } msg->len = BFN_GET(LPC_CAN->IF2_MCTRL, CANIFn_MCTRL_DLC); // TODO: If > 8, len = 8 msg->data[0] = BFN_GET(LPC_CAN->IF2_DA1, CANIFn_DA1_DATA0); msg->data[1] = BFN_GET(LPC_CAN->IF2_DA1, CANIFn_DA1_DATA1); msg->data[2] = BFN_GET(LPC_CAN->IF2_DA2, CANIFn_DA2_DATA2); msg->data[3] = BFN_GET(LPC_CAN->IF2_DA2, CANIFn_DA2_DATA3); msg->data[4] = BFN_GET(LPC_CAN->IF2_DB1, CANIFn_DB1_DATA4); msg->data[5] = BFN_GET(LPC_CAN->IF2_DB1, CANIFn_DB1_DATA5); msg->data[6] = BFN_GET(LPC_CAN->IF2_DB2, CANIFn_DB2_DATA6); msg->data[7] = BFN_GET(LPC_CAN->IF2_DB2, CANIFn_DB2_DATA7); LPC_CAN->STAT &= ~(CANSTAT_RXOK); return 1; } return 0; } void can_reset(can_t *obj) { LPC_SYSCON->PRESETCTRL &= ~PRESETCTRL_CAN_RST_N; LPC_CAN->STAT = 0; can_config_rxmsgobj(obj); } unsigned char can_rderror(can_t *obj) { return BFN_GET(LPC_CAN->EC, CANEC_REC); } unsigned char can_tderror(can_t *obj) { return BFN_GET(LPC_CAN->EC, CANEC_TEC); } void can_monitor(can_t *obj, int silent) { if (silent) { LPC_CAN->CNTL |= CANCNTL_TEST; LPC_CAN->TEST |= CANTEST_SILENT; } else { LPC_CAN->CNTL &= ~(CANCNTL_TEST); LPC_CAN->TEST &= ~CANTEST_SILENT; } if (!(LPC_CAN->CNTL & CANCNTL_INIT)) { LPC_CAN->CNTL |= CANCNTL_INIT; } }