Figuring out how to do board setup and reset

firmware/PIMORONI_YUKON/board_init.c

@@ -0,0 +1,50 @@
+#include "hardware/gpio.h"
+#include "hardware/i2c.h"
+#include "drivers/tca9555/tca9555.h"
+
+void board_init() {
+    gpio_init(8);
+    gpio_set_dir(8, GPIO_OUT);
+    gpio_put(8, true);
+    configure_i2c();
+    gpio_put(8, false);
+
+    gpio_init(9);
+    gpio_set_dir(9, GPIO_OUT);
+    gpio_put(9, true);
+    sleep_us(100);
+    gpio_put(9, false);
+    sleep_us(10);
+    gpio_put(9, true);
+    // Set the first IO expander's initial state
+    tca_set_output_port(0, 0x0000);
+    tca_set_polarity_port(0, 0x0000);
+    tca_set_config_port(0, 0x07BF);
+
+    // Set the second IO expander's initial state
+    tca_set_output_port(1, 0x0000);
+    tca_set_polarity_port(1, 0x0000);
+    tca_set_config_port(1, 0xFCE6);
+    sleep_us(100);
+    gpio_put(9, false);
+}
+
+void board_reset(void) {
+    for (int i = 0; i < 24; ++i) {
+        gpio_init(i);
+        hw_clear_bits(&padsbank0_hw->io[i], PADS_BANK0_GPIO0_IE_BITS |
+            PADS_BANK0_GPIO0_PUE_BITS |
+            PADS_BANK0_GPIO0_PDE_BITS);
+        hw_set_bits(&padsbank0_hw->io[i], PADS_BANK0_GPIO0_OD_BITS);
+    }
+
+    // Set the first IO expander's initial state
+    tca_set_output_port(0, 0x0000);
+    tca_set_polarity_port(0, 0x0000);
+    tca_set_config_port(0, 0x07BF);
+
+    // Set the second IO expander's initial state
+    tca_set_output_port(1, 0x0000);
+    tca_set_polarity_port(1, 0x0000);
+    tca_set_config_port(1, 0xFCE6);
+}

firmware/PIMORONI_YUKON/mpconfigboard.cmake

@@ -4,6 +4,10 @@ set(MICROPY_BOARD "pimoroni_yukon")
 # Allow Pico SDK to locate "pimoroni_yukon.h" in this directory.
 list(APPEND PICO_BOARD_HEADER_DIRS "${CMAKE_CURRENT_LIST_DIR}")
 
+set(MICROPY_SOURCE_BOARD
+    ${CMAKE_CURRENT_LIST_DIR}/board_init.c
+)
+
 # Board specific version of the frozen manifest
 set(MICROPY_FROZEN_MANIFEST ${CMAKE_CURRENT_LIST_DIR}/manifest.py)
 

firmware/PIMORONI_YUKON/mpconfigboard.h

@@ -9,6 +9,9 @@
 #define MICROPY_HW_SPI0_MOSI (0)
 #define MICROPY_HW_SPI0_MISO (0)
 
+#define MICROPY_HW_I2C0_SDA (24)
+#define MICROPY_HW_I2C0_SCL (25)
+
 // Enable networking.
 //#define MICROPY_PY_NETWORK 1
 //#define MICROPY_PY_NETWORK_HOSTNAME_DEFAULT     "Yukon"
@@ -23,6 +26,13 @@
 // Debug level (0-4) 1=warning, 2=info, 3=debug, 4=verbose
 // #define MODUSSL_MBEDTLS_DEBUG_LEVEL 1
 
-//#define MICROPY_HW_PIN_EXT_COUNT    CYW43_WL_GPIO_COUNT
+#define MICROPY_PY_TCA9555 (1)
+#define MICROPY_HW_PIN_EXT_COUNT    (32)
+
+//#define MICROPY_HW_PIN_RESERVED(i) ((i) == CYW43_PIN_WL_HOST_WAKE || (i) == CYW43_PIN_WL_REG_ON)
+
+#define MICROPY_BOARD_EARLY_INIT board_init
+void board_init(void);
 
-//#define MICROPY_HW_PIN_RESERVED(i) ((i) == CYW43_PIN_WL_HOST_WAKE || (i) == CYW43_PIN_WL_REG_ON)
+#define MICROPY_BOARD_PRE_RUNTIME_RESET board_reset
+void board_reset(void);