diff --git a/board/boards/black.h b/board/boards/black.h
index 133c11fb2d..3403a0353f 100644
--- a/board/boards/black.h
+++ b/board/boards/black.h
@@ -57,39 +57,6 @@ static void black_set_usb_load_switch(bool enabled) {
   set_gpio_output(GPIOB, 1, !enabled);
 }
 
-static void black_set_can_mode(uint8_t mode) {
-  black_enable_can_transceiver(2U, false);
-  black_enable_can_transceiver(4U, false);
-  switch (mode) {
-    case CAN_MODE_NORMAL:
-    case CAN_MODE_OBD_CAN2:
-      if ((bool)(mode == CAN_MODE_NORMAL) != (bool)(harness.status == HARNESS_STATUS_FLIPPED)) {
-        // B12,B13: disable OBD mode
-        set_gpio_mode(GPIOB, 12, MODE_INPUT);
-        set_gpio_mode(GPIOB, 13, MODE_INPUT);
-
-        // B5,B6: normal CAN2 mode
-        set_gpio_alternate(GPIOB, 5, GPIO_AF9_CAN2);
-        set_gpio_alternate(GPIOB, 6, GPIO_AF9_CAN2);
-        black_enable_can_transceiver(2U, true);
-
-      } else {
-        // B5,B6: disable normal CAN2 mode
-        set_gpio_mode(GPIOB, 5, MODE_INPUT);
-        set_gpio_mode(GPIOB, 6, MODE_INPUT);
-
-        // B12,B13: OBD mode
-        set_gpio_alternate(GPIOB, 12, GPIO_AF9_CAN2);
-        set_gpio_alternate(GPIOB, 13, GPIO_AF9_CAN2);
-        black_enable_can_transceiver(4U, true);
-      }
-      break;
-    default:
-      print("Tried to set unsupported CAN mode: "); puth(mode); print("\n");
-      break;
-  }
-}
-
 static bool black_check_ignition(void){
   // ignition is checked through harness
   return harness_check_ignition();
@@ -102,41 +69,12 @@ static void black_init(void) {
   set_gpio_alternate(GPIOA, 8, GPIO_AF11_CAN3);
   set_gpio_alternate(GPIOA, 15, GPIO_AF11_CAN3);
 
-  // C0: OBD_SBU1 (orientation detection)
-  // C3: OBD_SBU2 (orientation detection)
-  set_gpio_mode(GPIOC, 0, MODE_ANALOG);
-  set_gpio_mode(GPIOC, 3, MODE_ANALOG);
-
   // GPS OFF
   set_gpio_output(GPIOC, 5, 0);
   set_gpio_output(GPIOC, 12, 0);
 
-  // C10: OBD_SBU1_RELAY (harness relay driving output)
-  // C11: OBD_SBU2_RELAY (harness relay driving output)
-  set_gpio_mode(GPIOC, 10, MODE_OUTPUT);
-  set_gpio_mode(GPIOC, 11, MODE_OUTPUT);
-  set_gpio_output_type(GPIOC, 10, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_output_type(GPIOC, 11, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_output(GPIOC, 10, 1);
-  set_gpio_output(GPIOC, 11, 1);
-
   // Turn on USB load switch.
   black_set_usb_load_switch(true);
-
-  // Initialize harness
-  harness_init();
-
-
-  // Enable CAN transceivers
-  black_enable_can_transceivers(true);
-
-  // Disable LEDs
-  black_set_led(LED_RED, false);
-  black_set_led(LED_GREEN, false);
-  black_set_led(LED_BLUE, false);
-
-  // Set normal CAN mode
-  black_set_can_mode(CAN_MODE_NORMAL);
 }
 
 static void black_init_bootloader(void) {
@@ -156,7 +94,15 @@ static harness_configuration black_harness_config = {
   .pin_relay_SBU1 = 10,
   .pin_relay_SBU2 = 11,
   .adc_channel_SBU1 = 10,
-  .adc_channel_SBU2 = 13
+  .adc_channel_SBU2 = 13,
+  .GPIO_CAN2_RX_NORMAL = GPIOB,
+  .GPIO_CAN2_TX_NORMAL = GPIOB,
+  .GPIO_CAN2_RX_FLIPPED = GPIOB,
+  .GPIO_CAN2_TX_FLIPPED = GPIOB,
+  .pin_CAN2_RX_NORMAL = 12,
+  .pin_CAN2_TX_NORMAL = 13,
+  .pin_CAN2_RX_FLIPPED = 5,
+  .pin_CAN2_TX_FLIPPED = 6
 };
 
 board board_black = {
@@ -175,7 +121,6 @@ board board_black = {
   .enable_can_transceiver = black_enable_can_transceiver,
   .enable_can_transceivers = black_enable_can_transceivers,
   .set_led = black_set_led,
-  .set_can_mode = black_set_can_mode,
   .check_ignition = black_check_ignition,
   .read_voltage_mV = white_read_voltage_mV,
   .read_current_mA = unused_read_current,
diff --git a/board/boards/board_declarations.h b/board/boards/board_declarations.h
index 61e9ce2d8e..99a1f21d64 100644
--- a/board/boards/board_declarations.h
+++ b/board/boards/board_declarations.h
@@ -15,7 +15,6 @@ typedef void (*board_init_bootloader)(void);
 typedef void (*board_enable_can_transceiver)(uint8_t transceiver, bool enabled);
 typedef void (*board_enable_can_transceivers)(bool enabled);
 typedef void (*board_set_led)(uint8_t color, bool enabled);
-typedef void (*board_set_can_mode)(uint8_t mode);
 typedef bool (*board_check_ignition)(void);
 typedef uint32_t (*board_read_voltage_mV)(void);
 typedef uint32_t (*board_read_current_mA)(void);
@@ -41,7 +40,6 @@ struct board {
   board_enable_can_transceiver enable_can_transceiver;
   board_enable_can_transceivers enable_can_transceivers;
   board_set_led set_led;
-  board_set_can_mode set_can_mode;
   board_check_ignition check_ignition;
   board_read_voltage_mV read_voltage_mV;
   board_read_current_mA read_current_mA;
diff --git a/board/boards/cuatro.h b/board/boards/cuatro.h
index 90d0627517..e514ea295b 100644
--- a/board/boards/cuatro.h
+++ b/board/boards/cuatro.h
@@ -80,7 +80,7 @@ static void cuatro_set_amp_enabled(bool enabled){
 }
 
 static void cuatro_init(void) {
-  red_chiplet_init();
+  common_init_gpio();
 
   // init LEDs as open drain
   set_gpio_output_type(GPIOE, 2, OUTPUT_TYPE_OPEN_DRAIN);
@@ -118,9 +118,6 @@ static void cuatro_init(void) {
   gpio_uart7_init();
   uart_init(&uart_ring_som_debug, 115200);
 
-  // SPI init
-  gpio_spi_init();
-
   // fan setup
   set_gpio_alternate(GPIOC, 8, GPIO_AF2_TIM3);
   register_set_bits(&(GPIOC->OTYPER), GPIO_OTYPER_OT8); // open drain
@@ -150,7 +147,7 @@ static void cuatro_init(void) {
 }
 
 board board_cuatro = {
-  .harness_config = &red_chiplet_harness_config,
+  .harness_config = &tres_harness_config,
   .has_obd = true,
   .has_spi = true,
   .has_canfd = true,
@@ -164,7 +161,6 @@ board board_cuatro = {
   .enable_can_transceiver = cuatro_enable_can_transceiver,
   .enable_can_transceivers = cuatro_enable_can_transceivers,
   .set_led = cuatro_set_led,
-  .set_can_mode = red_chiplet_set_can_mode,
   .check_ignition = red_check_ignition,
   .read_voltage_mV = cuatro_read_voltage_mV,
   .read_current_mA = cuatro_read_current_mA,
diff --git a/board/boards/dos.h b/board/boards/dos.h
index d96cee4ca4..bda207aec1 100644
--- a/board/boards/dos.h
+++ b/board/boards/dos.h
@@ -57,38 +57,6 @@ static void dos_set_bootkick(BootState state) {
   set_gpio_output(GPIOC, 4, state != BOOT_BOOTKICK);
 }
 
-static void dos_set_can_mode(uint8_t mode) {
-  dos_enable_can_transceiver(2U, false);
-  dos_enable_can_transceiver(4U, false);
-  switch (mode) {
-    case CAN_MODE_NORMAL:
-    case CAN_MODE_OBD_CAN2:
-      if ((bool)(mode == CAN_MODE_NORMAL) != (bool)(harness.status == HARNESS_STATUS_FLIPPED)) {
-        // B12,B13: disable OBD mode
-        set_gpio_mode(GPIOB, 12, MODE_INPUT);
-        set_gpio_mode(GPIOB, 13, MODE_INPUT);
-
-        // B5,B6: normal CAN2 mode
-        set_gpio_alternate(GPIOB, 5, GPIO_AF9_CAN2);
-        set_gpio_alternate(GPIOB, 6, GPIO_AF9_CAN2);
-        dos_enable_can_transceiver(2U, true);
-      } else {
-        // B5,B6: disable normal CAN2 mode
-        set_gpio_mode(GPIOB, 5, MODE_INPUT);
-        set_gpio_mode(GPIOB, 6, MODE_INPUT);
-
-        // B12,B13: OBD mode
-        set_gpio_alternate(GPIOB, 12, GPIO_AF9_CAN2);
-        set_gpio_alternate(GPIOB, 13, GPIO_AF9_CAN2);
-        dos_enable_can_transceiver(4U, true);
-      }
-      break;
-    default:
-      print("Tried to set unsupported CAN mode: "); puth(mode); print("\n");
-      break;
-  }
-}
-
 static bool dos_check_ignition(void){
   // ignition is checked through harness
   return harness_check_ignition();
@@ -117,25 +85,6 @@ static void dos_init(void) {
   set_gpio_alternate(GPIOA, 8, GPIO_AF11_CAN3);
   set_gpio_alternate(GPIOA, 15, GPIO_AF11_CAN3);
 
-  // C0: OBD_SBU1 (orientation detection)
-  // C3: OBD_SBU2 (orientation detection)
-  set_gpio_mode(GPIOC, 0, MODE_ANALOG);
-  set_gpio_mode(GPIOC, 3, MODE_ANALOG);
-
-  // C10: OBD_SBU1_RELAY (harness relay driving output)
-  // C11: OBD_SBU2_RELAY (harness relay driving output)
-  set_gpio_mode(GPIOC, 10, MODE_OUTPUT);
-  set_gpio_mode(GPIOC, 11, MODE_OUTPUT);
-  set_gpio_output_type(GPIOC, 10, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_output_type(GPIOC, 11, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_output(GPIOC, 10, 1);
-  set_gpio_output(GPIOC, 11, 1);
-
-#ifdef ENABLE_SPI
-  // SPI init
-  gpio_spi_init();
-#endif
-
   // C8: FAN PWM aka TIM3_CH3
   set_gpio_alternate(GPIOC, 8, GPIO_AF2_TIM3);
 
@@ -148,24 +97,9 @@ static void dos_init(void) {
   pwm_init(TIM4, 2);
   dos_set_ir_power(0U);
 
-  // Initialize harness
-  harness_init();
-
-
-  // Enable CAN transceivers
-  dos_enable_can_transceivers(true);
-
-  // Disable LEDs
-  dos_set_led(LED_RED, false);
-  dos_set_led(LED_GREEN, false);
-  dos_set_led(LED_BLUE, false);
-
   // Bootkick
   dos_set_bootkick(true);
 
-  // Set normal CAN mode
-  dos_set_can_mode(CAN_MODE_NORMAL);
-
   // Init clock source (camera strobe) using PWM
   clock_source_init();
 }
@@ -181,7 +115,15 @@ static harness_configuration dos_harness_config = {
   .pin_relay_SBU1 = 10,
   .pin_relay_SBU2 = 11,
   .adc_channel_SBU1 = 10,
-  .adc_channel_SBU2 = 13
+  .adc_channel_SBU2 = 13,
+  .GPIO_CAN2_RX_NORMAL = GPIOB,
+  .GPIO_CAN2_TX_NORMAL = GPIOB,
+  .GPIO_CAN2_RX_FLIPPED = GPIOB,
+  .GPIO_CAN2_TX_FLIPPED = GPIOB,
+  .pin_CAN2_RX_NORMAL = 12,
+  .pin_CAN2_TX_NORMAL = 13,
+  .pin_CAN2_RX_FLIPPED = 5,
+  .pin_CAN2_TX_FLIPPED = 6
 };
 
 board board_dos = {
@@ -203,7 +145,6 @@ board board_dos = {
   .enable_can_transceiver = dos_enable_can_transceiver,
   .enable_can_transceivers = dos_enable_can_transceivers,
   .set_led = dos_set_led,
-  .set_can_mode = dos_set_can_mode,
   .check_ignition = dos_check_ignition,
   .read_voltage_mV = white_read_voltage_mV,
   .read_current_mA = unused_read_current,
diff --git a/board/boards/grey.h b/board/boards/grey.h
index b3e40bc6fe..cfd98481ab 100644
--- a/board/boards/grey.h
+++ b/board/boards/grey.h
@@ -24,7 +24,6 @@ board board_grey = {
   .enable_can_transceiver = white_enable_can_transceiver,
   .enable_can_transceivers = white_enable_can_transceivers,
   .set_led = white_set_led,
-  .set_can_mode = white_set_can_mode,
   .check_ignition = white_check_ignition,
   .read_voltage_mV = white_read_voltage_mV,
   .read_current_mA = white_read_current_mA,
diff --git a/board/boards/red.h b/board/boards/red.h
index f1d8d9c44b..a6b04fe6b4 100644
--- a/board/boards/red.h
+++ b/board/boards/red.h
@@ -53,48 +53,6 @@ static void red_set_led(uint8_t color, bool enabled) {
   }
 }
 
-static void red_set_can_mode(uint8_t mode) {
-  red_enable_can_transceiver(2U, false);
-  red_enable_can_transceiver(4U, false);
-  switch (mode) {
-    case CAN_MODE_NORMAL:
-    case CAN_MODE_OBD_CAN2:
-      if ((bool)(mode == CAN_MODE_NORMAL) != (bool)(harness.status == HARNESS_STATUS_FLIPPED)) {
-        // B12,B13: disable normal mode
-        set_gpio_pullup(GPIOB, 12, PULL_NONE);
-        set_gpio_mode(GPIOB, 12, MODE_ANALOG);
-
-        set_gpio_pullup(GPIOB, 13, PULL_NONE);
-        set_gpio_mode(GPIOB, 13, MODE_ANALOG);
-
-        // B5,B6: FDCAN2 mode
-        set_gpio_pullup(GPIOB, 5, PULL_NONE);
-        set_gpio_alternate(GPIOB, 5, GPIO_AF9_FDCAN2);
-
-        set_gpio_pullup(GPIOB, 6, PULL_NONE);
-        set_gpio_alternate(GPIOB, 6, GPIO_AF9_FDCAN2);
-        red_enable_can_transceiver(2U, true);
-      } else {
-        // B5,B6: disable normal mode
-        set_gpio_pullup(GPIOB, 5, PULL_NONE);
-        set_gpio_mode(GPIOB, 5, MODE_ANALOG);
-
-        set_gpio_pullup(GPIOB, 6, PULL_NONE);
-        set_gpio_mode(GPIOB, 6, MODE_ANALOG);
-        // B12,B13: FDCAN2 mode
-        set_gpio_pullup(GPIOB, 12, PULL_NONE);
-        set_gpio_alternate(GPIOB, 12, GPIO_AF9_FDCAN2);
-
-        set_gpio_pullup(GPIOB, 13, PULL_NONE);
-        set_gpio_alternate(GPIOB, 13, GPIO_AF9_FDCAN2);
-        red_enable_can_transceiver(4U, true);
-      }
-      break;
-    default:
-      break;
-  }
-}
-
 static bool red_check_ignition(void) {
   // ignition is checked through harness
   return harness_check_ignition();
@@ -107,17 +65,6 @@ static uint32_t red_read_voltage_mV(void){
 static void red_init(void) {
   common_init_gpio();
 
-  //C10,C11 : OBD_SBU1_RELAY, OBD_SBU2_RELAY
-  set_gpio_output_type(GPIOC, 10, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_pullup(GPIOC, 10, PULL_NONE);
-  set_gpio_mode(GPIOC, 10, MODE_OUTPUT);
-  set_gpio_output(GPIOC, 10, 1);
-
-  set_gpio_output_type(GPIOC, 11, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_pullup(GPIOC, 11, PULL_NONE);
-  set_gpio_mode(GPIOC, 11, MODE_OUTPUT);
-  set_gpio_output(GPIOC, 11, 1);
-
   // G11,B3,D7,B4: transceiver enable
   set_gpio_pullup(GPIOG, 11, PULL_NONE);
   set_gpio_mode(GPIOG, 11, MODE_OUTPUT);
@@ -140,21 +87,6 @@ static void red_init(void) {
   set_gpio_pullup(GPIOB, 14, PULL_UP);
   set_gpio_mode(GPIOB, 14, MODE_OUTPUT);
   set_gpio_output(GPIOB, 14, 1);
-
-  // Initialize harness
-  harness_init();
-
-
-  // Enable CAN transceivers
-  red_enable_can_transceivers(true);
-
-  // Disable LEDs
-  red_set_led(LED_RED, false);
-  red_set_led(LED_GREEN, false);
-  red_set_led(LED_BLUE, false);
-
-  // Set normal CAN mode
-  red_set_can_mode(CAN_MODE_NORMAL);
 }
 
 static harness_configuration red_harness_config = {
@@ -168,7 +100,15 @@ static harness_configuration red_harness_config = {
   .pin_relay_SBU1 = 10,
   .pin_relay_SBU2 = 11,
   .adc_channel_SBU1 = 4, //ADC12_INP4
-  .adc_channel_SBU2 = 17 //ADC1_INP17
+  .adc_channel_SBU2 = 17, //ADC1_INP17
+  .GPIO_CAN2_RX_NORMAL = GPIOB,
+  .GPIO_CAN2_TX_NORMAL = GPIOB,
+  .GPIO_CAN2_RX_FLIPPED = GPIOB,
+  .GPIO_CAN2_TX_FLIPPED = GPIOB,
+  .pin_CAN2_RX_NORMAL = 12,
+  .pin_CAN2_TX_NORMAL = 13,
+  .pin_CAN2_RX_FLIPPED = 5,
+  .pin_CAN2_TX_FLIPPED = 6
 };
 
 board board_red = {
@@ -187,7 +127,6 @@ board board_red = {
   .enable_can_transceiver = red_enable_can_transceiver,
   .enable_can_transceivers = red_enable_can_transceivers,
   .set_led = red_set_led,
-  .set_can_mode = red_set_can_mode,
   .check_ignition = red_check_ignition,
   .read_voltage_mV = red_read_voltage_mV,
   .read_current_mA = unused_read_current,
diff --git a/board/boards/red_chiplet.h b/board/boards/red_chiplet.h
deleted file mode 100644
index e5d1aa097f..0000000000
--- a/board/boards/red_chiplet.h
+++ /dev/null
@@ -1,151 +0,0 @@
-#pragma once
-
-#include "board_declarations.h"
-
-// ///////////////////////////////////// //
-// Red Panda chiplet (STM32H7) + Harness //
-// ///////////////////////////////////// //
-
-// Most hardware functionality is similar to red panda
-
-static void red_chiplet_enable_can_transceiver(uint8_t transceiver, bool enabled) {
-  switch (transceiver) {
-    case 1U:
-      set_gpio_output(GPIOG, 11, !enabled);
-      break;
-    case 2U:
-      set_gpio_output(GPIOB, 10, !enabled);
-      break;
-    case 3U:
-      set_gpio_output(GPIOD, 7, !enabled);
-      break;
-    case 4U:
-      set_gpio_output(GPIOB, 11, !enabled);
-      break;
-    default:
-      break;
-  }
-}
-
-static void red_chiplet_enable_can_transceivers(bool enabled) {
-  uint8_t main_bus = (harness.status == HARNESS_STATUS_FLIPPED) ? 3U : 1U;
-  for (uint8_t i=1U; i<=4U; i++) {
-    // Leave main CAN always on for CAN-based ignition detection
-    if (i == main_bus) {
-      red_chiplet_enable_can_transceiver(i, true);
-    } else {
-      red_chiplet_enable_can_transceiver(i, enabled);
-    }
-  }
-}
-
-static void red_chiplet_set_can_mode(uint8_t mode) {
-  red_chiplet_enable_can_transceiver(2U, false);
-  red_chiplet_enable_can_transceiver(4U, false);
-  switch (mode) {
-    case CAN_MODE_NORMAL:
-    case CAN_MODE_OBD_CAN2:
-      if ((bool)(mode == CAN_MODE_NORMAL) != (bool)(harness.status == HARNESS_STATUS_FLIPPED)) {
-        // B12,B13: disable normal mode
-        set_gpio_pullup(GPIOB, 12, PULL_NONE);
-        set_gpio_mode(GPIOB, 12, MODE_ANALOG);
-
-        set_gpio_pullup(GPIOB, 13, PULL_NONE);
-        set_gpio_mode(GPIOB, 13, MODE_ANALOG);
-
-        // B5,B6: FDCAN2 mode
-        set_gpio_pullup(GPIOB, 5, PULL_NONE);
-        set_gpio_alternate(GPIOB, 5, GPIO_AF9_FDCAN2);
-
-        set_gpio_pullup(GPIOB, 6, PULL_NONE);
-        set_gpio_alternate(GPIOB, 6, GPIO_AF9_FDCAN2);
-        red_chiplet_enable_can_transceiver(2U, true);
-      } else {
-        // B5,B6: disable normal mode
-        set_gpio_pullup(GPIOB, 5, PULL_NONE);
-        set_gpio_mode(GPIOB, 5, MODE_ANALOG);
-
-        set_gpio_pullup(GPIOB, 6, PULL_NONE);
-        set_gpio_mode(GPIOB, 6, MODE_ANALOG);
-        // B12,B13: FDCAN2 mode
-        set_gpio_pullup(GPIOB, 12, PULL_NONE);
-        set_gpio_alternate(GPIOB, 12, GPIO_AF9_FDCAN2);
-
-        set_gpio_pullup(GPIOB, 13, PULL_NONE);
-        set_gpio_alternate(GPIOB, 13, GPIO_AF9_FDCAN2);
-        red_chiplet_enable_can_transceiver(4U, true);
-      }
-      break;
-    default:
-      break;
-  }
-}
-
-static void red_chiplet_set_fan_or_usb_load_switch(bool enabled) {
-  set_gpio_output(GPIOD, 3, enabled);
-}
-
-static void red_chiplet_init(void) {
-  common_init_gpio();
-
-  // A8, A3: OBD_SBU1_RELAY, OBD_SBU2_RELAY
-  set_gpio_output_type(GPIOA, 8, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_pullup(GPIOA, 8, PULL_NONE);
-  set_gpio_output(GPIOA, 8, 1);
-  set_gpio_mode(GPIOA, 8, MODE_OUTPUT);
-
-  set_gpio_output_type(GPIOA, 3, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_pullup(GPIOA, 3, PULL_NONE);
-  set_gpio_output(GPIOA, 3, 1);
-  set_gpio_mode(GPIOA, 3, MODE_OUTPUT);
-
-  // G11,B10,D7,B11: transceiver enable
-  set_gpio_pullup(GPIOG, 11, PULL_NONE);
-  set_gpio_mode(GPIOG, 11, MODE_OUTPUT);
-
-  set_gpio_pullup(GPIOB, 10, PULL_NONE);
-  set_gpio_mode(GPIOB, 10, MODE_OUTPUT);
-
-  set_gpio_pullup(GPIOD, 7, PULL_NONE);
-  set_gpio_mode(GPIOD, 7, MODE_OUTPUT);
-
-  set_gpio_pullup(GPIOB, 11, PULL_NONE);
-  set_gpio_mode(GPIOB, 11, MODE_OUTPUT);
-
-  // D3: usb load switch
-  set_gpio_pullup(GPIOD, 3, PULL_NONE);
-  set_gpio_mode(GPIOD, 3, MODE_OUTPUT);
-
-  // B0: 5VOUT_S
-  set_gpio_pullup(GPIOB, 0, PULL_NONE);
-  set_gpio_mode(GPIOB, 0, MODE_ANALOG);
-
-  // Initialize harness
-  harness_init();
-
-
-  // Enable CAN transceivers
-  red_chiplet_enable_can_transceivers(true);
-
-  // Disable LEDs
-  red_set_led(LED_RED, false);
-  red_set_led(LED_GREEN, false);
-  red_set_led(LED_BLUE, false);
-
-  // Set normal CAN mode
-  red_chiplet_set_can_mode(CAN_MODE_NORMAL);
-}
-
-static harness_configuration red_chiplet_harness_config = {
-  .has_harness = true,
-  .GPIO_SBU1 = GPIOC,
-  .GPIO_SBU2 = GPIOA,
-  .GPIO_relay_SBU1 = GPIOA,
-  .GPIO_relay_SBU2 = GPIOA,
-  .pin_SBU1 = 4,
-  .pin_SBU2 = 1,
-  .pin_relay_SBU1 = 8,
-  .pin_relay_SBU2 = 3,
-  .adc_channel_SBU1 = 4, // ADC12_INP4
-  .adc_channel_SBU2 = 17 // ADC1_INP17
-};
diff --git a/board/boards/tres.h b/board/boards/tres.h
index f0602ae60b..3919b8e52c 100644
--- a/board/boards/tres.h
+++ b/board/boards/tres.h
@@ -9,7 +9,7 @@
 static bool tres_ir_enabled;
 static bool tres_fan_enabled;
 static void tres_update_fan_ir_power(void) {
-  red_chiplet_set_fan_or_usb_load_switch(tres_ir_enabled || tres_fan_enabled);
+  set_gpio_output(GPIOD, 3, tres_ir_enabled || tres_fan_enabled);
 }
 
 static void tres_set_ir_power(uint8_t percentage){
@@ -29,6 +29,37 @@ static void tres_set_fan_enabled(bool enabled) {
   tres_update_fan_ir_power();
 }
 
+static void tres_enable_can_transceiver(uint8_t transceiver, bool enabled) {
+  switch (transceiver) {
+    case 1U:
+      set_gpio_output(GPIOG, 11, !enabled);
+      break;
+    case 2U:
+      set_gpio_output(GPIOB, 10, !enabled);
+      break;
+    case 3U:
+      set_gpio_output(GPIOD, 7, !enabled);
+      break;
+    case 4U:
+      set_gpio_output(GPIOB, 11, !enabled);
+      break;
+    default:
+      break;
+  }
+}
+
+static void tres_enable_can_transceivers(bool enabled) {
+  uint8_t main_bus = (harness.status == HARNESS_STATUS_FLIPPED) ? 3U : 1U;
+  for (uint8_t i=1U; i<=4U; i++) {
+    // Leave main CAN always on for CAN-based ignition detection
+    if (i == main_bus) {
+      tres_enable_can_transceiver(i, true);
+    } else {
+      tres_enable_can_transceiver(i, enabled);
+    }
+  }
+}
+
 static bool tres_read_som_gpio (void) {
   return (get_gpio_input(GPIOC, 2) != 0);
 }
@@ -39,7 +70,7 @@ static void tres_init(void) {
   register_set_bits(&(PWR->CR3), PWR_CR3_USB33DEN);
   while ((PWR->CR3 & PWR_CR3_USB33RDY) == 0U);
 
-  red_chiplet_init();
+  common_init_gpio();
 
   // C2: SOM GPIO used as input (fan control at boot)
   set_gpio_mode(GPIOC, 2, MODE_INPUT);
@@ -54,9 +85,6 @@ static void tres_init(void) {
   gpio_uart7_init();
   uart_init(&uart_ring_som_debug, 115200);
 
-  // SPI init
-  gpio_spi_init();
-
   // fan setup
   set_gpio_alternate(GPIOC, 8, GPIO_AF2_TIM3);
 
@@ -74,8 +102,30 @@ static void tres_init(void) {
   clock_source_init();
 }
 
+static harness_configuration tres_harness_config = {
+  .has_harness = true,
+  .GPIO_SBU1 = GPIOC,
+  .GPIO_SBU2 = GPIOA,
+  .GPIO_relay_SBU1 = GPIOA,
+  .GPIO_relay_SBU2 = GPIOA,
+  .pin_SBU1 = 4,
+  .pin_SBU2 = 1,
+  .pin_relay_SBU1 = 8,
+  .pin_relay_SBU2 = 3,
+  .adc_channel_SBU1 = 4, // ADC12_INP4
+  .adc_channel_SBU2 = 17, // ADC1_INP17
+  .GPIO_CAN2_RX_NORMAL = GPIOB,
+  .GPIO_CAN2_TX_NORMAL = GPIOB,
+  .GPIO_CAN2_RX_FLIPPED = GPIOB,
+  .GPIO_CAN2_TX_FLIPPED = GPIOB,
+  .pin_CAN2_RX_NORMAL = 12,
+  .pin_CAN2_TX_NORMAL = 13,
+  .pin_CAN2_RX_FLIPPED = 5,
+  .pin_CAN2_TX_FLIPPED = 6
+};
+
 board board_tres = {
-  .harness_config = &red_chiplet_harness_config,
+  .harness_config = &tres_harness_config,
   .has_obd = true,
   .has_spi = true,
   .has_canfd = true,
@@ -86,10 +136,9 @@ board board_tres = {
   .fan_enable_cooldown_time = 3U,
   .init = tres_init,
   .init_bootloader = unused_init_bootloader,
-  .enable_can_transceiver = red_chiplet_enable_can_transceiver,
-  .enable_can_transceivers = red_chiplet_enable_can_transceivers,
+  .enable_can_transceiver = tres_enable_can_transceiver,
+  .enable_can_transceivers = tres_enable_can_transceivers,
   .set_led = red_set_led,
-  .set_can_mode = red_chiplet_set_can_mode,
   .check_ignition = red_check_ignition,
   .read_voltage_mV = red_read_voltage_mV,
   .read_current_mA = unused_read_current,
diff --git a/board/boards/uno.h b/board/boards/uno.h
index d1728f1f9f..d033db7648 100644
--- a/board/boards/uno.h
+++ b/board/boards/uno.h
@@ -62,38 +62,6 @@ static void uno_set_bootkick(BootState state) {
   }
 }
 
-static void uno_set_can_mode(uint8_t mode) {
-  uno_enable_can_transceiver(2U, false);
-  uno_enable_can_transceiver(4U, false);
-  switch (mode) {
-    case CAN_MODE_NORMAL:
-    case CAN_MODE_OBD_CAN2:
-      if ((bool)(mode == CAN_MODE_NORMAL) != (bool)(harness.status == HARNESS_STATUS_FLIPPED)) {
-        // B12,B13: disable OBD mode
-        set_gpio_mode(GPIOB, 12, MODE_INPUT);
-        set_gpio_mode(GPIOB, 13, MODE_INPUT);
-
-        // B5,B6: normal CAN2 mode
-        set_gpio_alternate(GPIOB, 5, GPIO_AF9_CAN2);
-        set_gpio_alternate(GPIOB, 6, GPIO_AF9_CAN2);
-        uno_enable_can_transceiver(2U, true);
-      } else {
-        // B5,B6: disable normal CAN2 mode
-        set_gpio_mode(GPIOB, 5, MODE_INPUT);
-        set_gpio_mode(GPIOB, 6, MODE_INPUT);
-
-        // B12,B13: OBD mode
-        set_gpio_alternate(GPIOB, 12, GPIO_AF9_CAN2);
-        set_gpio_alternate(GPIOB, 13, GPIO_AF9_CAN2);
-        uno_enable_can_transceiver(4U, true);
-      }
-      break;
-    default:
-      print("Tried to set unsupported CAN mode: "); puth(mode); print("\n");
-      break;
-  }
-}
-
 static bool uno_check_ignition(void){
   // ignition is checked through harness
   return harness_check_ignition();
@@ -118,25 +86,11 @@ static void uno_init(void) {
   set_gpio_alternate(GPIOA, 8, GPIO_AF11_CAN3);
   set_gpio_alternate(GPIOA, 15, GPIO_AF11_CAN3);
 
-  // C0: OBD_SBU1 (orientation detection)
-  // C3: OBD_SBU2 (orientation detection)
-  set_gpio_mode(GPIOC, 0, MODE_ANALOG);
-  set_gpio_mode(GPIOC, 3, MODE_ANALOG);
-
   // GPS off
   set_gpio_output(GPIOB, 1, 0);
   set_gpio_output(GPIOC, 5, 0);
   set_gpio_output(GPIOC, 12, 0);
 
-  // C10: OBD_SBU1_RELAY (harness relay driving output)
-  // C11: OBD_SBU2_RELAY (harness relay driving output)
-  set_gpio_mode(GPIOC, 10, MODE_OUTPUT);
-  set_gpio_mode(GPIOC, 11, MODE_OUTPUT);
-  set_gpio_output_type(GPIOC, 10, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_output_type(GPIOC, 11, OUTPUT_TYPE_OPEN_DRAIN);
-  set_gpio_output(GPIOC, 10, 1);
-  set_gpio_output(GPIOC, 11, 1);
-
   // C8: FAN PWM aka TIM3_CH3
   set_gpio_alternate(GPIOC, 8, GPIO_AF2_TIM3);
 
@@ -148,21 +102,6 @@ static void uno_init(void) {
   pwm_init(TIM4, 2);
   uno_set_ir_power(0U);
 
-  // Initialize harness
-  harness_init();
-
-
-  // Enable CAN transceivers
-  uno_enable_can_transceivers(true);
-
-  // Disable LEDs
-  uno_set_led(LED_RED, false);
-  uno_set_led(LED_GREEN, false);
-  uno_set_led(LED_BLUE, false);
-
-  // Set normal CAN mode
-  uno_set_can_mode(CAN_MODE_NORMAL);
-
   // Switch to phone usb mode if harness connection is powered by less than 7V
   if(white_read_voltage_mV() < 7000U){
     uno_set_usb_switch(true);
@@ -192,7 +131,15 @@ static harness_configuration uno_harness_config = {
   .pin_relay_SBU1 = 10,
   .pin_relay_SBU2 = 11,
   .adc_channel_SBU1 = 10,
-  .adc_channel_SBU2 = 13
+  .adc_channel_SBU2 = 13,
+  .GPIO_CAN2_RX_NORMAL = GPIOB,
+  .GPIO_CAN2_TX_NORMAL = GPIOB,
+  .GPIO_CAN2_RX_FLIPPED = GPIOB,
+  .GPIO_CAN2_TX_FLIPPED = GPIOB,
+  .pin_CAN2_RX_NORMAL = 12,
+  .pin_CAN2_TX_NORMAL = 13,
+  .pin_CAN2_RX_FLIPPED = 5,
+  .pin_CAN2_TX_FLIPPED = 6
 };
 
 board board_uno = {
@@ -210,7 +157,6 @@ board board_uno = {
   .enable_can_transceiver = uno_enable_can_transceiver,
   .enable_can_transceivers = uno_enable_can_transceivers,
   .set_led = uno_set_led,
-  .set_can_mode = uno_set_can_mode,
   .check_ignition = uno_check_ignition,
   .read_voltage_mV = white_read_voltage_mV,
   .read_current_mA = unused_read_current,
diff --git a/board/boards/white.h b/board/boards/white.h
index c4a2559353..795d8ad946 100644
--- a/board/boards/white.h
+++ b/board/boards/white.h
@@ -69,26 +69,6 @@ static void white_set_usb_power_mode(uint8_t mode){
   }
 }
 
-static void white_set_can_mode(uint8_t mode){
-  if (mode == CAN_MODE_NORMAL) {
-    // B12,B13: disable GMLAN mode
-    set_gpio_mode(GPIOB, 12, MODE_INPUT);
-    set_gpio_mode(GPIOB, 13, MODE_INPUT);
-
-    // B3,B4: disable GMLAN mode
-    set_gpio_mode(GPIOB, 3, MODE_INPUT);
-    set_gpio_mode(GPIOB, 4, MODE_INPUT);
-
-    // B5,B6: normal CAN2 mode
-    set_gpio_alternate(GPIOB, 5, GPIO_AF9_CAN2);
-    set_gpio_alternate(GPIOB, 6, GPIO_AF9_CAN2);
-
-    // A8,A15: normal CAN3 mode
-    set_gpio_alternate(GPIOA, 8, GPIO_AF11_CAN3);
-    set_gpio_alternate(GPIOA, 15, GPIO_AF11_CAN3);
-  }
-}
-
 static uint32_t white_read_voltage_mV(void){
   return adc_get_mV(12) * 11U;
 }
@@ -152,17 +132,21 @@ static void white_grey_init(void) {
   set_gpio_alternate(GPIOC, 11, GPIO_AF7_USART3);
   set_gpio_pullup(GPIOC, 11, PULL_UP);
 
+  // B12,B13: disable GMLAN mode
+  set_gpio_mode(GPIOB, 12, MODE_INPUT);
+  set_gpio_mode(GPIOB, 13, MODE_INPUT);
 
-  // Enable CAN transceivers
-  white_enable_can_transceivers(true);
+  // B3,B4: disable GMLAN mode
+  set_gpio_mode(GPIOB, 3, MODE_INPUT);
+  set_gpio_mode(GPIOB, 4, MODE_INPUT);
 
-  // Disable LEDs
-  white_set_led(LED_RED, false);
-  white_set_led(LED_GREEN, false);
-  white_set_led(LED_BLUE, false);
+  // B5,B6: normal CAN2 mode
+  set_gpio_alternate(GPIOB, 5, GPIO_AF9_CAN2);
+  set_gpio_alternate(GPIOB, 6, GPIO_AF9_CAN2);
 
-  // Set normal CAN mode
-  white_set_can_mode(CAN_MODE_NORMAL);
+  // A8,A15: normal CAN3 mode
+  set_gpio_alternate(GPIOA, 8, GPIO_AF11_CAN3);
+  set_gpio_alternate(GPIOA, 15, GPIO_AF11_CAN3);
 
   // Init usb power mode
   // Init in CDP mode only if panda is powered by 12V.
@@ -204,7 +188,6 @@ board board_white = {
   .enable_can_transceiver = white_enable_can_transceiver,
   .enable_can_transceivers = white_enable_can_transceivers,
   .set_led = white_set_led,
-  .set_can_mode = white_set_can_mode,
   .check_ignition = white_check_ignition,
   .read_voltage_mV = white_read_voltage_mV,
   .read_current_mA = white_read_current_mA,
diff --git a/board/drivers/harness.h b/board/drivers/harness.h
index cfb6965c03..44c54da738 100644
--- a/board/drivers/harness.h
+++ b/board/drivers/harness.h
@@ -32,6 +32,37 @@ void set_intercept_relay(bool intercept, bool ignition_relay) {
   }
 }
 
+void set_can_mode(uint8_t mode) {
+  current_board->enable_can_transceiver(2U, false);
+  current_board->enable_can_transceiver(4U, false);
+  switch (mode) {
+    case CAN_MODE_NORMAL:
+    case CAN_MODE_OBD_CAN2:
+      if ((bool)(mode == CAN_MODE_NORMAL) != (bool)(harness.status == HARNESS_STATUS_FLIPPED)) {
+        // normal pins
+        set_gpio_mode(current_board->harness_config->GPIO_CAN2_RX_NORMAL, current_board->harness_config->pin_CAN2_RX_NORMAL, MODE_ANALOG);
+        set_gpio_mode(current_board->harness_config->GPIO_CAN2_TX_NORMAL, current_board->harness_config->pin_CAN2_TX_NORMAL, MODE_ANALOG);
+
+        // flipped pins
+        set_gpio_mode(current_board->harness_config->GPIO_CAN2_RX_FLIPPED, current_board->harness_config->pin_CAN2_RX_FLIPPED, GPIO_CAN2_AF);
+        set_gpio_mode(current_board->harness_config->GPIO_CAN2_TX_FLIPPED, current_board->harness_config->pin_CAN2_TX_FLIPPED, GPIO_CAN2_AF);
+        current_board->enable_can_transceiver(2U, true);
+      } else {
+        // normal pins
+        set_gpio_mode(current_board->harness_config->GPIO_CAN2_RX_FLIPPED, current_board->harness_config->pin_CAN2_RX_FLIPPED, MODE_ANALOG);
+        set_gpio_mode(current_board->harness_config->GPIO_CAN2_TX_FLIPPED, current_board->harness_config->pin_CAN2_TX_FLIPPED, MODE_ANALOG);
+
+        // flipped pins
+        set_gpio_mode(current_board->harness_config->GPIO_CAN2_RX_NORMAL, current_board->harness_config->pin_CAN2_RX_NORMAL, GPIO_CAN2_AF);
+        set_gpio_mode(current_board->harness_config->GPIO_CAN2_TX_NORMAL, current_board->harness_config->pin_CAN2_TX_NORMAL, GPIO_CAN2_AF);
+        current_board->enable_can_transceiver(4U, true);
+      }
+      break;
+    default:
+      break;
+  }
+}
+
 bool harness_check_ignition(void) {
   bool ret = false;
 
@@ -94,6 +125,14 @@ void harness_tick(void) {
 }
 
 void harness_init(void) {
+  set_can_mode(CAN_MODE_NORMAL);
+
+  // init OBD_SBUx_RELAY
+  set_gpio_output_type(current_board->harness_config->GPIO_relay_SBU1, current_board->harness_config->pin_relay_SBU1, OUTPUT_TYPE_OPEN_DRAIN);
+  set_gpio_output_type(current_board->harness_config->GPIO_relay_SBU2, current_board->harness_config->pin_relay_SBU2, OUTPUT_TYPE_OPEN_DRAIN);
+  set_gpio_output(current_board->harness_config->GPIO_relay_SBU1, current_board->harness_config->pin_relay_SBU1, 1);
+  set_gpio_output(current_board->harness_config->GPIO_relay_SBU2, current_board->harness_config->pin_relay_SBU2, 1);
+
   // try to detect orientation
   harness.status = harness_detect_orientation();
   if (harness.status != HARNESS_STATUS_NC) {
diff --git a/board/drivers/harness_declarations.h b/board/drivers/harness_declarations.h
index 953941f621..0f2828a2a3 100644
--- a/board/drivers/harness_declarations.h
+++ b/board/drivers/harness_declarations.h
@@ -15,6 +15,8 @@ extern struct harness_t harness;
 
 struct harness_configuration {
   const bool has_harness;
+
+  // harness control
   GPIO_TypeDef * const GPIO_SBU1;
   GPIO_TypeDef * const GPIO_SBU2;
   GPIO_TypeDef * const GPIO_relay_SBU1;
@@ -25,6 +27,16 @@ struct harness_configuration {
   const uint8_t pin_relay_SBU2;
   const uint8_t adc_channel_SBU1;
   const uint8_t adc_channel_SBU2;
+
+  // CAN control
+  GPIO_TypeDef * const GPIO_CAN2_RX_NORMAL;
+  GPIO_TypeDef * const GPIO_CAN2_TX_NORMAL;
+  GPIO_TypeDef * const GPIO_CAN2_RX_FLIPPED;
+  GPIO_TypeDef * const GPIO_CAN2_TX_FLIPPED;
+  const uint8_t pin_CAN2_RX_NORMAL;
+  const uint8_t pin_CAN2_TX_NORMAL;
+  const uint8_t pin_CAN2_RX_FLIPPED;
+  const uint8_t pin_CAN2_TX_FLIPPED;
 };
 
 // The ignition relay is only used for testing purposes
diff --git a/board/main.c b/board/main.c
index aaea95d089..edfa36c07f 100644
--- a/board/main.c
+++ b/board/main.c
@@ -77,14 +77,14 @@ void set_safety_mode(uint16_t mode, uint16_t param) {
     case SAFETY_SILENT:
       set_intercept_relay(false, false);
       if (current_board->has_obd) {
-        current_board->set_can_mode(CAN_MODE_NORMAL);
+        set_can_mode(CAN_MODE_NORMAL);
       }
       can_silent = ALL_CAN_SILENT;
       break;
     case SAFETY_NOOUTPUT:
       set_intercept_relay(false, false);
       if (current_board->has_obd) {
-        current_board->set_can_mode(CAN_MODE_NORMAL);
+        set_can_mode(CAN_MODE_NORMAL);
       }
       can_silent = ALL_CAN_LIVE;
       break;
@@ -97,9 +97,9 @@ void set_safety_mode(uint16_t mode, uint16_t param) {
         // TODO: rewrite using hardware queues rather than fifo to cancel specific messages
         can_clear_send(CANIF_FROM_CAN_NUM(1), 1);
         if (param == 0U) {
-          current_board->set_can_mode(CAN_MODE_OBD_CAN2);
+          set_can_mode(CAN_MODE_OBD_CAN2);
         } else {
-          current_board->set_can_mode(CAN_MODE_NORMAL);
+          set_can_mode(CAN_MODE_NORMAL);
         }
       }
       can_silent = ALL_CAN_LIVE;
@@ -109,7 +109,7 @@ void set_safety_mode(uint16_t mode, uint16_t param) {
       heartbeat_counter = 0U;
       heartbeat_lost = false;
       if (current_board->has_obd) {
-        current_board->set_can_mode(CAN_MODE_NORMAL);
+        set_can_mode(CAN_MODE_NORMAL);
       }
       can_silent = ALL_CAN_LIVE;
       break;
@@ -322,6 +322,9 @@ int main(void) {
 
   // init board
   current_board->init();
+  if (current_board->harness_config->has_harness) {
+    harness_init();
+  }
 
   // panda has an FPU, let's use it!
   enable_fpu();
@@ -354,12 +357,14 @@ int main(void) {
 
 #ifdef ENABLE_SPI
   if (current_board->has_spi) {
+    gpio_spi_init();
     spi_init();
   }
 #endif
 
   current_board->set_led(LED_RED, false);
   current_board->set_led(LED_GREEN, false);
+  current_board->set_led(LED_BLUE, false);
 
   print("**** INTERRUPTS ON ****\n");
   enable_interrupts();
diff --git a/board/main_comms.h b/board/main_comms.h
index e366b19a09..88b0af65bf 100644
--- a/board/main_comms.h
+++ b/board/main_comms.h
@@ -215,10 +215,10 @@ int comms_control_handler(ControlPacket_t *req, uint8_t *resp) {
       if (current_board->has_obd) {
         if (req->param1 == 1U) {
           // Enable OBD CAN
-          current_board->set_can_mode(CAN_MODE_OBD_CAN2);
+          set_can_mode(CAN_MODE_OBD_CAN2);
         } else {
           // Disable OBD CAN
-          current_board->set_can_mode(CAN_MODE_NORMAL);
+          set_can_mode(CAN_MODE_NORMAL);
         }
       }
       break;
diff --git a/board/stm32f4/stm32f4_config.h b/board/stm32f4/stm32f4_config.h
index eae9222a9d..726e8198b2 100644
--- a/board/stm32f4/stm32f4_config.h
+++ b/board/stm32f4/stm32f4_config.h
@@ -12,6 +12,7 @@
 
 // Around (1Mbps / 8 bits/byte / 12 bytes per message)
 #define CAN_INTERRUPT_RATE 12000U
+#define GPIO_CAN2_AF GPIO_AF9_CAN2
 
 #define MAX_LED_FADE 8192U
 
diff --git a/board/stm32h7/board.h b/board/stm32h7/board.h
index ea4812245e..143e431c74 100644
--- a/board/stm32h7/board.h
+++ b/board/stm32h7/board.h
@@ -15,7 +15,6 @@
 #include "stm32h7/sound.h"
 #include "drivers/clock_source.h"
 #include "boards/red.h"
-#include "boards/red_chiplet.h"
 #include "boards/tres.h"
 #include "boards/cuatro.h"
 
diff --git a/board/stm32h7/peripherals.h b/board/stm32h7/peripherals.h
index c6874b8ac3..222f3c0dc3 100644
--- a/board/stm32h7/peripherals.h
+++ b/board/stm32h7/peripherals.h
@@ -44,13 +44,6 @@ void common_init_gpio(void) {
   set_gpio_mode(GPIOE, 4, MODE_OUTPUT);
   set_gpio_output_type(GPIOE, 4, OUTPUT_TYPE_OPEN_DRAIN);
 
-  //C4,A1: OBD_SBU1, OBD_SBU2
-  set_gpio_pullup(GPIOC, 4, PULL_NONE);
-  set_gpio_mode(GPIOC, 4, MODE_ANALOG);
-
-  set_gpio_pullup(GPIOA, 1, PULL_NONE);
-  set_gpio_mode(GPIOA, 1, MODE_ANALOG);
-
   //F11: VOLT_S
   set_gpio_pullup(GPIOF, 11, PULL_NONE);
   set_gpio_mode(GPIOF, 11, MODE_ANALOG);
diff --git a/board/stm32h7/stm32h7_config.h b/board/stm32h7/stm32h7_config.h
index bfc12e8c3a..e60b8da34f 100644
--- a/board/stm32h7/stm32h7_config.h
+++ b/board/stm32h7/stm32h7_config.h
@@ -24,6 +24,7 @@ separate IRQs for RX and TX.
 1 / ((29 bits / 0.5Mbps) + (23 bits / 2Mbps)) = 14388Hz
 */
 #define CAN_INTERRUPT_RATE 16000U
+#define GPIO_CAN2_AF GPIO_AF9_FDCAN2
 
 #define MAX_LED_FADE 10240U