Setup flash pins on Sparkfun SAMD51 Micromod

Author: stonehippo

ports/atmel-samd/boards/sparkfun_samd51_micromod/board.c

@@ -26,6 +26,9 @@
 
 #include "supervisor/board.h"
 #include "mpconfigboard.h"
+#include "common-hal/microcontroller/Pin.h"
+#include "hal/include/hal_gpio.h"
+#include "py/mphal.h"
 
 void board_init(void) {
 }
@@ -39,3 +42,23 @@ void reset_board(void) {
 
 void board_deinit(void) {
 }
+
+void external_flash_setup(void) {
+    // Do not reset the external flash write-protect and hold pins high
+    never_reset_pin_number(PIN_PB22);
+    never_reset_pin_number(PIN_PB23);
+
+    // note: using output instead of input+pullups because the pullups are a little weak
+    // Set the WP pin high
+    gpio_set_pin_function(PIN_PB22, GPIO_PIN_FUNCTION_OFF);
+    gpio_set_pin_direction(PIN_PB22, GPIO_DIRECTION_OUT);
+    gpio_set_pin_level(PIN_PB22, true);
+
+    // Set the HOLD pin high
+    gpio_set_pin_function(PIN_PB23, GPIO_PIN_FUNCTION_OFF);
+    gpio_set_pin_direction(PIN_PB23, GPIO_DIRECTION_OUT);
+    gpio_set_pin_level(PIN_PB23, true);
+
+    // Add some delay to give the pins time to get set
+    // mp_hal_delay_ms(3000);
+}

ports/atmel-samd/boards/sparkfun_samd51_micromod/mpconfigboard.h

@@ -27,3 +27,7 @@
 // USB is always used internally so skip the pin objects for it.
 #define IGNORE_PIN_PA24     1
 #define IGNORE_PIN_PA25     1
+
+// The external flash chip has WP (write-protect) and hold pins we should ignore
+#define IGNORE_PIN_PB22
+#define IGNORE_PIN_PB23

ports/atmel-samd/boards/sparkfun_samd51_micromod/mpconfigboard.mk

@@ -13,3 +13,4 @@ EXTERNAL_FLASH_DEVICES = W25Q128JVxM
 LONGINT_IMPL = MPZ
 
 CIRCUITPY_PS2IO = 1
+CIRCUITPY_EXTERNAL_FLASH_SETUP = 1