fixup examples based on default pin #define-s and also support them being undefined

Author: kilograham

dma/channel_irq/channel_irq.c

@@ -52,6 +52,9 @@ void dma_handler() {
 }
 
 int main() {
+#ifndef PICO_DEFAULT_LED_PIN
+#warning dma/channel_irq example requires a board with a regular LED
+#else
     // Set up a PIO state machine to serialise our bits
     uint offset = pio_add_program(pio0, &pio_serialiser_program);
     pio_serialiser_program_init(pio0, 0, offset, PICO_DEFAULT_LED_PIN, PIO_SERIAL_CLKDIV);
@@ -87,5 +90,5 @@ int main() {
     // time to sit and think about its early retirement -- maybe open a bakery?
     while (true)
         tight_loop_contents();
-
+#endif
 }

dma/control_blocks/control_blocks.c

@@ -47,6 +47,9 @@ const struct {uint32_t len; const char *data;} control_blocks[] = {
 };
 
 int main() {
+#ifndef uart_default
+#warning dma/control_blocks example requires a UART
+#else
     stdio_init_all();
     puts("DMA control block example:");
 
@@ -81,7 +84,7 @@ int main() {
 
     c = dma_channel_get_default_config(data_chan);
     channel_config_set_transfer_data_size(&c, DMA_SIZE_8);
-    channel_config_set_dreq(&c, DREQ_UART0_TX + 2 * PICO_DEFAULT_UART);
+    channel_config_set_dreq(&c, DREQ_UART0_TX + 2 * uart_get_index(uart_default));
     // Trigger ctrl_chan when data_chan completes
     channel_config_set_chain_to(&c, ctrl_chan);
     // Raise the IRQ flag when 0 is written to a trigger register (end of chain):
@@ -90,7 +93,7 @@ int main() {
     dma_channel_configure(
         data_chan,
         &c,
-        &(PICO_DEFAULT_UART ? uart1_hw : uart0_hw)->dr,
+        &uart_get_hw(uart_default)->dr,
         NULL,           // Initial read address and transfer count are unimportant;
         0,              // the control channel will reprogram them each time.
         false           // Don't start yet.
@@ -108,4 +111,5 @@ int main() {
     dma_hw->ints0 = 1u << data_chan;
 
     puts("DMA finished.");
+#endif
 }

flash/nuke/nuke.c

@@ -26,12 +26,20 @@
 #include "pico/bootrom.h"
 
 int main() {
-    flash_range_erase(0, PICO_FLASH_SIZE_BYTES);
+    uint flash_size_bytes;
+#ifndef PICO_FLASH_SIZE_BYTES
+#warning PICO_FLASH_SIZE_BYTES not set, assuming 16M
+    flash_size_bytes = 16 * 1024 * 1024;
+#else
+    flash_size_bytes = PICO_FLASH_SIZE_BYTES;
+#endif
+    flash_range_erase(0, flash_size_bytes);
     // Leave an eyecatcher pattern in the first page of flash so picotool can
     // more easily check the size:
     static const uint8_t eyecatcher[FLASH_PAGE_SIZE] = "NUKE";
     flash_range_program(0, eyecatcher, FLASH_PAGE_SIZE);
 
+#ifdef PICO_DEFAULT_LED_PIN
     // Flash LED for success
     gpio_init(PICO_DEFAULT_LED_PIN);
     gpio_set_dir(PICO_DEFAULT_LED_PIN, GPIO_OUT);
@@ -41,6 +49,7 @@ int main() {
         gpio_put(PICO_DEFAULT_LED_PIN, 0);
         sleep_ms(100);
     }
+#endif
 
     // Pop back up as an MSD drive
     reset_usb_boot(0, 0);

gpio/dht_sensor/dht.c

@@ -9,7 +9,10 @@
 #include "pico/stdlib.h"
 #include "hardware/gpio.h"
 
-const uint LED_PIN = PICO_DEFAULT_LED_PIN;
+#ifdef PICO_DEFAULT_LED_PIN
+#define LED_PIN PICO_DEFAULT_LED_PIN
+#endif
+
 const uint DHT_PIN = 15;
 const uint MAX_TIMINGS = 85;
 
@@ -22,9 +25,11 @@ void read_from_dht(dht_reading *result);
 
 int main() {
     stdio_init_all();
-    gpio_init(LED_PIN);
     gpio_init(DHT_PIN);
+#ifdef LED_PIN
+    gpio_init(LED_PIN);
     gpio_set_dir(LED_PIN, GPIO_OUT);
+#endif
     while (1) {
         dht_reading reading;
         read_from_dht(&reading);
@@ -46,7 +51,9 @@ void read_from_dht(dht_reading *result) {
     sleep_ms(20);
     gpio_set_dir(DHT_PIN, GPIO_IN);
 
+#ifdef LED_PIN
     gpio_put(LED_PIN, 1);
+#endif
     for (uint i = 0; i < MAX_TIMINGS; i++) {
         uint count = 0;
         while (gpio_get(DHT_PIN) == last) {
@@ -63,7 +70,9 @@ void read_from_dht(dht_reading *result) {
             j++;
         }
     }
+#ifdef LED_PIN
     gpio_put(LED_PIN, 0);
+#endif
 
     if ((j >= 40) && (data[4] == ((data[0] + data[1] + data[2] + data[3]) & 0xFF))) {
         result->humidity = (float) ((data[0] << 8) + data[1]) / 10;

i2c/bus_scan/bus_scan.c

@@ -22,6 +22,7 @@
 
 #include <stdio.h>
 #include "pico/stdlib.h"
+#include "pico/binary_info.h"
 #include "hardware/i2c.h"
 
 // I2C reserves some addresses for special purposes. We exclude these from the scan.
@@ -33,13 +34,18 @@ bool reserved_addr(uint8_t addr) {
 int main() {
     // Enable UART so we can print status output
     stdio_init_all();
-
-    // This example will use I2C0 on GPIO4 (SDA) and GPIO5 (SCL)
-    i2c_init(i2c0, 100 * 1000);
-    gpio_set_function(4, GPIO_FUNC_I2C);
-    gpio_set_function(5, GPIO_FUNC_I2C);
-    gpio_pull_up(4);
-    gpio_pull_up(5);
+#if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
+#warning i2c/bus_scane example requires a board with I2C pins
+    puts("Default I2C pins were not defined");
+#else
+    // This example will use I2C0 on the default SDA and SCL pins (4, 5 on a Pico)
+    i2c_init(i2c_default, 100 * 1000);
+    gpio_set_function(PICO_DEFAULT_I2C_SDA_PIN, GPIO_FUNC_I2C);
+    gpio_set_function(PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C);
+    gpio_pull_up(PICO_DEFAULT_I2C_SDA_PIN);
+    gpio_pull_up(PICO_DEFAULT_I2C_SCL_PIN);
+    // Make the I2C pins available to picotool
+    bi_decl(bi_2pins_with_func(PICO_DEFAULT_I2C_SDA_PIN, PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C));
 
     printf("\nI2C Bus Scan\n");
     printf("   0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F\n");
@@ -67,4 +73,5 @@ int main() {
     }
     printf("Done.\n");
     return 0;
+#endif
 }

i2c/lcd_1602_i2c/lcd_1602_i2c.c

@@ -58,7 +58,6 @@ const int LCD_BACKLIGHT = 0x08;
 
 const int LCD_ENABLE_BIT = 0x04;
 
-#define I2C_PORT i2c0
 // By default these LCD display drivers are on bus address 0x27
 static int addr = 0x27;
 
@@ -71,7 +70,9 @@ static int addr = 0x27;
 
 /* Quick helper function for single byte transfers */
 void i2c_write_byte(uint8_t val) {
-    i2c_write_blocking(I2C_PORT, addr, &val, 1, false);
+#ifdef i2c_default
+    i2c_write_blocking(i2c_default, addr, &val, 1, false);
+#endif
 }
 
 void lcd_toggle_enable(uint8_t val) {
@@ -129,14 +130,17 @@ void lcd_init() {
 }
 
 int main() {
-    // This example will use I2C0 on GPIO4 (SDA) and GPIO5 (SCL)
-    i2c_init(I2C_PORT, 100 * 1000);
-    gpio_set_function(4, GPIO_FUNC_I2C);
-    gpio_set_function(5, GPIO_FUNC_I2C);
-    gpio_pull_up(4);
-    gpio_pull_up(5);
+#if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
+    #warning i2c/bus_scane example requires a board with I2C pins
+#else
+    // This example will use I2C0 on the default SDA and SCL pins (4, 5 on a Pico)
+    i2c_init(i2c_default, 100 * 1000);
+    gpio_set_function(PICO_DEFAULT_I2C_SDA_PIN, GPIO_FUNC_I2C);
+    gpio_set_function(PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C);
+    gpio_pull_up(PICO_DEFAULT_I2C_SDA_PIN);
+    gpio_pull_up(PICO_DEFAULT_I2C_SCL_PIN);
     // Make the I2C pins available to picotool
-    bi_decl( bi_2pins_with_func(4, 5, GPIO_FUNC_I2C));
+    bi_decl(bi_2pins_with_func(PICO_DEFAULT_I2C_SDA_PIN, PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C));
 
     lcd_init();
 
@@ -161,4 +165,5 @@ int main() {
     }
 
     return 0;
+#endif
 }

i2c/mpu6050_i2c/mpu6050_i2c.c

@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <string.h>
 #include "pico/stdlib.h"
+#include "pico/binary_info.h"
 #include "hardware/i2c.h"
 
 /* Example code to talk to a MPU6050 MEMS accelerometer and gyroscope
@@ -23,22 +24,21 @@
 
    Connections on Raspberry Pi Pico board, other boards may vary.
 
-   GPIO 4 (pin 6)-> SDA on MPU6050 board
-   GPIO 5 (pin 7)-> SCL on MPU6050 board
+   GPIO PICO_DEFAULT_I2C_SDA_PIN (On Pico this is 4 (pin 6)) -> SDA on MPU6050 board
+   GPIO PICO_DEFAULT_I2C_SCK_PIN (On Pico this is 5 (pin 7)) -> SCL on MPU6050 board
    3.3v (pin 36) -> VCC on MPU6050 board
    GND (pin 38)  -> GND on MPU6050 board
 */
 
 // By default these devices  are on bus address 0x68
 static int addr = 0x68;
 
-#define I2C_PORT i2c0
-
+#ifdef i2c_default
 static void mpu6050_reset() {
     // Two byte reset. First byte register, second byte data
     // There are a load more options to set up the device in different ways that could be added here
     uint8_t buf[] = {0x6B, 0x00};
-    i2c_write_blocking(I2C_PORT, addr, buf, 2, false);
+    i2c_write_blocking(i2c_default, addr, buf, 2, false);
 }
 
 static void mpu6050_read_raw(int16_t accel[3], int16_t gyro[3], int16_t *temp) {
@@ -50,8 +50,8 @@ static void mpu6050_read_raw(int16_t accel[3], int16_t gyro[3], int16_t *temp) {
 
     // Start reading acceleration registers from register 0x3B for 6 bytes
     uint8_t val = 0x3B;
-    i2c_write_blocking(I2C_PORT, addr, &val, 1, true); // true to keep master control of bus
-    i2c_read_blocking(I2C_PORT, addr, buffer, 6, false);
+    i2c_write_blocking(i2c_default, addr, &val, 1, true); // true to keep master control of bus
+    i2c_read_blocking(i2c_default, addr, buffer, 6, false);
 
     for (int i = 0; i < 3; i++) {
         accel[i] = (buffer[i * 2] << 8 | buffer[(i * 2) + 1]);
@@ -60,8 +60,8 @@ static void mpu6050_read_raw(int16_t accel[3], int16_t gyro[3], int16_t *temp) {
     // Now gyro data from reg 0x43 for 6 bytes
     // The register is auto incrementing on each read
     val = 0x43;
-    i2c_write_blocking(I2C_PORT, addr, &val, 1, true);
-    i2c_read_blocking(I2C_PORT, addr, buffer, 6, false);  // False - finished with bus
+    i2c_write_blocking(i2c_default, addr, &val, 1, true);
+    i2c_read_blocking(i2c_default, addr, buffer, 6, false);  // False - finished with bus
 
     for (int i = 0; i < 3; i++) {
         gyro[i] = (buffer[i * 2] << 8 | buffer[(i * 2) + 1]);;
@@ -70,23 +70,29 @@ static void mpu6050_read_raw(int16_t accel[3], int16_t gyro[3], int16_t *temp) {
     // Now temperature from reg 0x41 for 2 bytes
     // The register is auto incrementing on each read
     val = 0x41;
-    i2c_write_blocking(I2C_PORT, addr, &val, 1, true);
-    i2c_read_blocking(I2C_PORT, addr, buffer, 2, false);  // False - finished with bus
+    i2c_write_blocking(i2c_default, addr, &val, 1, true);
+    i2c_read_blocking(i2c_default, addr, buffer, 2, false);  // False - finished with bus
 
     *temp = buffer[0] << 8 | buffer[1];
 }
+#endif
 
 int main() {
     stdio_init_all();
-
+#if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
+    #warning i2c/bus_scane example requires a board with I2C pins
+    puts("Default I2C pins were not defined');
+#else
     printf("Hello, MPU6050! Reading raw data from registers...\n");
 
-    // This example will use I2C0 on GPIO4 (SDA) and GPIO5 (SCL) running at 400kHz.
-    i2c_init(I2C_PORT, 400 * 1000);
-    gpio_set_function(4, GPIO_FUNC_I2C);
-    gpio_set_function(5, GPIO_FUNC_I2C);
-    gpio_pull_up(4);
-    gpio_pull_up(5);
+    // This example will use I2C0 on the default SDA and SCL pins (4, 5 on a Pico)
+    i2c_init(i2c_default, 400 * 1000);
+    gpio_set_function(PICO_DEFAULT_I2C_SDA_PIN, GPIO_FUNC_I2C);
+    gpio_set_function(PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C);
+    gpio_pull_up(PICO_DEFAULT_I2C_SDA_PIN);
+    gpio_pull_up(PICO_DEFAULT_I2C_SCL_PIN);
+    // Make the I2C pins available to picotool
+    bi_decl(bi_2pins_with_func(PICO_DEFAULT_I2C_SDA_PIN, PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C));
 
     mpu6050_reset();
 
@@ -106,5 +112,6 @@ int main() {
         sleep_ms(100);
     }
 
+#endif
     return 0;
 }

picoboard/button/button.c

@@ -11,7 +11,7 @@
 #include "hardware/structs/ioqspi.h"
 #include "hardware/structs/sio.h"
 
-// This example blinks the Picoboard LED when the BOOTSEL button is pressed.
+// This example blinks the Pico LED when the BOOTSEL button is pressed.
 //
 // Picoboard has a button attached to the flash CS pin, which the bootrom
 // checks, and jumps straight to the USB bootcode if the button is pressed
@@ -53,10 +53,14 @@ bool __no_inline_not_in_flash_func(get_bootsel_button)() {
 }
 
 int main() {
+#ifndef PICO_DEFAULT_LED_PIN
+#warning picobooard/button example requires a board with a regular LED
+#else
     gpio_init(PICO_DEFAULT_LED_PIN);
     gpio_set_dir(PICO_DEFAULT_LED_PIN, GPIO_OUT);
     while (true) {
-        gpio_put(PICO_DEFAULT_LED_PIN, get_bootsel_button());
+        gpio_put(PICO_DEFAULT_LED_PIN, get_bootsel_button() ^ PICO_DEFAULT_LED_PIN_INVERTED);
         sleep_ms(10);
     }
-}
+#endif
+}

pio/hello_pio/hello.c

@@ -10,6 +10,9 @@
 #include "hello.pio.h"
 
 int main() {
+#ifndef PICO_DEFAULT_LED_PIN
+#warning pio/hello_pio example requires a board with a regular LED
+#else
     // Choose which PIO instance to use (there are two instances)
     PIO pio = pio0;
 
@@ -35,4 +38,5 @@ int main() {
         pio_sm_put_blocking(pio, sm, 0);
         sleep_ms(500);
     }
+#endif
 }

pwm/led_fade/pwm_led_fade.c

@@ -13,6 +13,7 @@
 #include "hardware/irq.h"
 #include "hardware/pwm.h"
 
+#ifdef PICO_DEFAULT_LED_PIN
 void on_pwm_wrap() {
     static int fade = 0;
     static bool going_up = true;
@@ -36,8 +37,12 @@ void on_pwm_wrap() {
     // Note this range matches with the wrap value
     pwm_set_gpio_level(PICO_DEFAULT_LED_PIN, fade * fade);
 }
+#endif
 
 int main() {
+#ifndef PICO_DEFAULT_LED_PIN
+#warning pwm/led_fade example requires a board with a regular LED
+#else
     // Tell the LED pin that the PWM is in charge of its value.
     gpio_set_function(PICO_DEFAULT_LED_PIN, GPIO_FUNC_PWM);
     // Figure out which slice we just connected to the LED pin
@@ -62,4 +67,5 @@ int main() {
     // can twiddle our thumbs
     while (1)
         tight_loop_contents();
+#endif
 }