seb/saltylab-firmware
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

fix: guard TWAI tx against bus-off and fix recovery state machine

Browse Source 
Three bugs blocked CAN forwarding when UART commands were received:
1. vesc_can_send_rpm had no g_twai_bus_off guard, flooding failed
   twai_transmit calls during BUS_OFF/RECOVERING states.
2. Recovery only handled TWAI_STATE_BUS_OFF; RECOVERING and STOPPED
   states were unhandled, leaving g_twai_bus_off=false while TWAI
   was still unusable.
3. No startup delay after twai_start() — VESC not yet ready to ACK
   caused immediate TEC runup to BUS_OFF at boot.

Fix: bus-off guard in send_rpm, full state machine in rx_task
(BUS_OFF→initiate, STOPPED→start, RECOVERING→wait), 200ms post-
start delay in vesc_can_init().

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
This commit is contained in:
sl-firmware 2026-04-20 11:28:36 -04:00 committed by Sebastien Vayrette
parent dd52982a03
commit 34a937628d
1 changed files with 27 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
esp32s3/balance/main/vesc_can.c
View File

@ -39,17 +39,22 @@ void vesc_can_init(void)
twai_timing_config_t tcfg = TWAI_TIMING_CONFIG_500KBITS(); twai_timing_config_t tcfg = TWAI_TIMING_CONFIG_500KBITS();
twai_filter_config_t fcfg = TWAI_FILTER_CONFIG_ACCEPT_ALL(); twai_filter_config_t fcfg = TWAI_FILTER_CONFIG_ACCEPT_ALL();
ESP_LOGI(TAG, "TWAI: twai_driver_install tx=%d rx=%d 500kbps", VESC_CAN_TX_GPIO, VESC_CAN_RX_GPIO); gcfg.tx_queue_len = 5;
ESP_LOGI(TAG, "TWAI: installing driver tx=%d rx=%d 500kbps", VESC_CAN_TX_GPIO, VESC_CAN_RX_GPIO);
ESP_ERROR_CHECK(twai_driver_install(&gcfg, &tcfg, &fcfg)); ESP_ERROR_CHECK(twai_driver_install(&gcfg, &tcfg, &fcfg));
ESP_LOGI(TAG, "TWAI: driver installed OK"); ESP_LOGI(TAG, "TWAI: driver installed OK");
ESP_LOGI(TAG, "TWAI: twai_start");
ESP_ERROR_CHECK(twai_start()); ESP_ERROR_CHECK(twai_start());
/* Wait for VESC to join the bus before drive_task begins TX — prevents
* immediate TEC runup and BUS_OFF if VESC CAN isn't ready at ESP32 boot. */
vTaskDelay(pdMS_TO_TICKS(200));
ESP_LOGI(TAG, "TWAI: started OK — bus active"); ESP_LOGI(TAG, "TWAI: started OK — bus active");
} }
void vesc_can_send_rpm(uint8_t vesc_id, int32_t erpm) void vesc_can_send_rpm(uint8_t vesc_id, int32_t erpm)
{ {
if (g_twai_bus_off) { return; }
uint32_t ext_id = ((uint32_t)VESC_PKT_SET_RPM << 8u) | vesc_id; uint32_t ext_id = ((uint32_t)VESC_PKT_SET_RPM << 8u) | vesc_id;
twai_message_t msg = { twai_message_t msg = {
.extd = 1, .extd = 1,
@ -81,12 +86,29 @@ void vesc_can_rx_task(void *arg)
} }
twai_status_info_t si; twai_status_info_t si;
if (twai_get_status_info(&si) == ESP_OK) { if (twai_get_status_info(&si) == ESP_OK) {
g_twai_bus_off = (si.state == TWAI_STATE_BUS_OFF); /* Mark bus-off for ANY non-running state so vesc_can_send_rpm
if (g_twai_bus_off) { * won't flood with failed transmits during recovery. */
ESP_LOGE(TAG, "TWAI BUS OFF — tx_err=%lu rx_err=%lu", g_twai_bus_off = (si.state != TWAI_STATE_RUNNING);
if (si.state == TWAI_STATE_BUS_OFF) {
ESP_LOGE(TAG, "TWAI BUS OFF tx_err=%lu rx_err=%lu — recovering",
(unsigned long)si.tx_error_counter, (unsigned long)si.rx_error_counter); (unsigned long)si.tx_error_counter, (unsigned long)si.rx_error_counter);
twai_initiate_recovery();
/* Driver auto-transitions RECOVERING→STOPPED after 128 recessive
* bit occurrences (~3 ms min at 500kbps); 100 ms is safe headroom. */
vTaskDelay(pdMS_TO_TICKS(100));
} else if (si.state == TWAI_STATE_STOPPED) {
/* Recovery completed — restart the driver. */
esp_err_t serr = twai_start();
if (serr == ESP_OK) {
g_twai_bus_off = false;
ESP_LOGI(TAG, "TWAI recovered — bus active");
} else {
ESP_LOGE(TAG, "TWAI restart failed 0x%x", serr);
} }
} }
/* TWAI_STATE_RECOVERING: initiation already called, just wait. */
}
continue; continue;
} }
ESP_LOGI(TAG, "twai_receive OK id=0x%08" PRIx32 " dlc=%u", msg.identifier, msg.data_length_code); ESP_LOGI(TAG, "twai_receive OK id=0x%08" PRIx32 " dlc=%u", msg.identifier, msg.data_length_code);