/* * This file is part of the canonmanage project. * Copyright 2023 Edward V. Emelianov . * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include "can.h" #include // REMAPPED to PB8/PB9!!! #include // memcpy // circular buffer for received messages static CAN_message messages[CAN_INMESSAGE_SIZE]; static uint8_t first_free_idx = 0; // index of first empty cell static int8_t first_nonfree_idx = -1; // index of first data cell static uint16_t oldspeed = 0, oldID = 0; static void can_process_fifo(uint8_t fifo_num); // push next message into buffer; return 1 if buffer overfull static int CAN_messagebuf_push(CAN_message *msg){ if(first_free_idx == first_nonfree_idx){ return 1; // no free space } if(first_nonfree_idx < 0) first_nonfree_idx = 0; // first message in empty buffer memcpy(&messages[first_free_idx++], msg, sizeof(CAN_message)); // need to roll? if(first_free_idx == CAN_INMESSAGE_SIZE) first_free_idx = 0; return 0; } // pop message from buffer CAN_message *CAN_messagebuf_pop(){ if(first_nonfree_idx < 0) return NULL; CAN_message *msg = &messages[first_nonfree_idx++]; if(first_nonfree_idx == CAN_INMESSAGE_SIZE) first_nonfree_idx = 0; if(first_nonfree_idx == first_free_idx){ // buffer is empty - refresh it first_nonfree_idx = -1; first_free_idx = 0; } return msg; } // speed - in kbps, ID - identificator void CAN_setup(uint16_t speed, uint16_t ID){ if(speed == 0) return; // didn't initialized yet if(speed < 25) speed = 25; else if(speed > 3000) speed = 3000; oldspeed = speed; oldID = ID; uint32_t tmout = 16000000; // Configure GPIO: PB8 - CAN_Rx, PB9 - CAN_Tx /* (1) Select AF mode (10) on PB8 and PB9 */ /* (2) AF4 for CAN signals */ RCC->APB2ENR |= RCC_APB2ENR_AFIOEN | RCC_APB2ENR_IOPBEN; AFIO->MAPR |= AFIO_MAPR_CAN_REMAP_REMAP2; GPIOB->CRH = 0; //pin_set(GPIOB, 1<<8); GPIOB->CRH = (GPIOB->CRH & ~(CRH(8,0xf)|CRH(9,0xf))) | CRH(8, CNF_FLINPUT | MODE_INPUT) | CRH(9, CNF_AFPP | MODE_NORMAL); /* Enable the peripheral clock CAN */ RCC->APB1ENR |= RCC_APB1ENR_CAN1EN; CAN1->MCR |= CAN_MCR_INRQ; while((CAN1->MSR & CAN_MSR_INAK) != CAN_MSR_INAK) if(--tmout == 0) break; CAN1->MCR &=~ CAN_MCR_SLEEP; CAN1->MCR |= CAN_MCR_ABOM; /* allow automatically bus-off */ CAN1->BTR = 2 << 20 | 3 << 16 | (4500/speed - 1); CAN1->MCR &= ~CAN_MCR_INRQ; tmout = 16000000; while((CAN1->MSR & CAN_MSR_INAK) == CAN_MSR_INAK) if(--tmout == 0) break; // accept ALL CAN1->FMR = CAN_FMR_FINIT; CAN1->FM1R = CAN_FM1R_FBM0; // filter in list mode CAN1->FA1R = CAN_FA1R_FACT0; // activate filter0 CAN1->sFilterRegister[0].FR1 = ID; CAN1->FFA1R = 1; // filter 0 for FIFO1 CAN1->FMR &= ~CAN_FMR_FINIT; /* (12) */ CAN1->IER |= CAN_IER_ERRIE | CAN_IER_FOVIE0 | CAN_IER_FOVIE1 | CAN_IER_BOFIE; /* Configure IT */ NVIC_SetPriority(USB_LP_CAN1_RX0_IRQn, 0); // RX FIFO0 IRQ NVIC_SetPriority(CAN1_RX1_IRQn, 0); // RX FIFO1 IRQ NVIC_SetPriority(CAN1_SCE_IRQn, 0); // RX status changed IRQ NVIC_EnableIRQ(USB_LP_CAN1_RX0_IRQn); NVIC_EnableIRQ(CAN1_RX1_IRQn); NVIC_EnableIRQ(CAN1_SCE_IRQn); CAN1->MSR = 0; // clear SLAKI, WKUI, ERRI } void can_proc(){ // check for messages in FIFO0 & FIFO1 if(CAN1->RF0R & CAN_RF0R_FMP0){ can_process_fifo(0); } if(CAN1->RF1R & CAN_RF1R_FMP1){ can_process_fifo(1); } IWDG->KR = IWDG_REFRESH; if(CAN1->ESR & (CAN_ESR_BOFF | CAN_ESR_EPVF | CAN_ESR_EWGF)){ // much errors - restart CAN BUS // request abort for all mailboxes CAN1->TSR |= CAN_TSR_ABRQ0 | CAN_TSR_ABRQ1 | CAN_TSR_ABRQ2; // reset CAN bus RCC->APB1RSTR |= RCC_APB1RSTR_CAN1RST; RCC->APB1RSTR &= ~RCC_APB1RSTR_CAN1RST; CAN_setup(oldspeed, oldID); } } CAN_status can_send(uint8_t *msg, uint8_t len, uint16_t target_id){ uint8_t mailbox = 0; // check first free mailbox if(CAN1->TSR & (CAN_TSR_TME)){ mailbox = (CAN1->TSR & CAN_TSR_CODE) >> 24; }else{ // no free mailboxes return CAN_BUSY; } CAN_TxMailBox_TypeDef *box = &CAN1->sTxMailBox[mailbox]; uint32_t lb = 0, hb = 0; switch(len){ case 8: hb |= (uint32_t)msg[7] << 24; __attribute__((fallthrough)); case 7: hb |= (uint32_t)msg[6] << 16; __attribute__((fallthrough)); case 6: hb |= (uint32_t)msg[5] << 8; __attribute__((fallthrough)); case 5: hb |= (uint32_t)msg[4]; __attribute__((fallthrough)); case 4: lb |= (uint32_t)msg[3] << 24; __attribute__((fallthrough)); case 3: lb |= (uint32_t)msg[2] << 16; __attribute__((fallthrough)); case 2: lb |= (uint32_t)msg[1] << 8; __attribute__((fallthrough)); default: lb |= (uint32_t)msg[0]; } box->TDLR = lb; box->TDHR = hb; box->TDTR = len; box->TIR = (target_id & 0x7FF) << 21 | CAN_TI0R_TXRQ; return CAN_OK; } static void can_process_fifo(uint8_t fifo_num){ if(fifo_num > 1) return; CAN_FIFOMailBox_TypeDef *box = &CAN1->sFIFOMailBox[fifo_num]; volatile uint32_t *RFxR = (fifo_num) ? &CAN1->RF1R : &CAN1->RF0R; // read all while(*RFxR & CAN_RF0R_FMP0){ // amount of messages pending // CAN_RDTxR: (16-31) - timestamp, (8-15) - filter match index, (0-3) - data length /* TODO: check filter match index if more than one ID can receive */ CAN_message msg; uint8_t *dat = msg.data; uint8_t len = box->RDTR & 0x0f; msg.length = len; msg.ID = box->RIR >> 21; if(len){ // message can be without data uint32_t hb = box->RDHR, lb = box->RDLR; switch(len){ case 8: dat[7] = hb>>24; __attribute__((fallthrough)); case 7: dat[6] = (hb>>16) & 0xff; __attribute__((fallthrough)); case 6: dat[5] = (hb>>8) & 0xff; __attribute__((fallthrough)); case 5: dat[4] = hb & 0xff; __attribute__((fallthrough)); case 4: dat[3] = lb>>24; __attribute__((fallthrough)); case 3: dat[2] = (lb>>16) & 0xff; __attribute__((fallthrough)); case 2: dat[1] = (lb>>8) & 0xff; __attribute__((fallthrough)); case 1: dat[0] = lb & 0xff; } } if(CAN_messagebuf_push(&msg)) return; // error: buffer is full, try later *RFxR |= CAN_RF0R_RFOM0; // release fifo for access to next message } *RFxR = 0; // clear FOVR & FULL } void can_rx1_isr(){ // Rx FIFO1 (overrun) if(CAN1->RF1R & CAN_RF1R_FOVR1){ CAN1->RF1R &= ~CAN_RF1R_FOVR1; } } void can_sce_isr(){ // status changed if(CAN1->MSR & CAN_MSR_ERRI){ // Error CAN1->MSR &= ~CAN_MSR_ERRI; // request abort for problem mailbox if(CAN1->TSR & CAN_TSR_TERR0) CAN1->TSR |= CAN_TSR_ABRQ0; if(CAN1->TSR & CAN_TSR_TERR1) CAN1->TSR |= CAN_TSR_ABRQ1; if(CAN1->TSR & CAN_TSR_TERR2) CAN1->TSR |= CAN_TSR_ABRQ2; } }