#include <stdio.h> #include "pico/stdlib.h" #include "hardware/gpio.h" #include "hardware/adc.h" #define N_SAMPLES 1000 uint16_t sample_buf[N_SAMPLES]; void printhelp() { puts("\nCommands:"); puts("c0, ...\t: Select ADC channel n"); puts("s\t: Sample once"); puts("S\t: Sample many"); puts("w\t: Wiggle pins"); } void __not_in_flash_func(adc_capture)(uint16_t *buf, size_t count) { adc_fifo_setup(true, false, 0, false, false); adc_run(true); for (size_t i = 0; i < count; i = i + 1) buf[i] = adc_fifo_get_blocking(); adc_run(false); adc_fifo_drain(); } int main(void) { stdio_init_all(); adc_init(); adc_set_temp_sensor_enabled(true); // Set all pins to input (as far as SIO is concerned) gpio_set_dir_all_bits(0); for (int i = 2; i < 30; ++i) { gpio_set_function(i, GPIO_FUNC_SIO); if (i >= 26) { gpio_disable_pulls(i); gpio_set_input_enabled(i, false); } } printf("\n===========================\n"); printf("RP2040 ADC and Test Console\n"); printf("===========================\n"); printhelp(); while (1) { char c = getchar(); printf("%c", c); switch (c) { case 'c': c = getchar(); printf("%c\n", c); if (c < '0' || c > '7') { printf("Unknown input channel\n"); printhelp(); } else { adc_select_input(c - '0'); printf("Switched to channel %c\n", c); } break; case 's': { uint32_t result = adc_read(); const float conversion_factor = 3.3f / (1 << 12); printf("\n0x%03x -> %f V\n", result, result * conversion_factor); break; } case 'S': { printf("\nStarting capture\n"); adc_capture(sample_buf, N_SAMPLES); printf("Done\n"); for (int i = 0; i < N_SAMPLES; i = i + 1) printf("%03x\n", sample_buf[i]); break; } case 'w': { printf("\nPress any key to stop wiggling\n"); int i = 1; gpio_set_dir_all_bits(-1); while (getchar_timeout_us(0) == PICO_ERROR_TIMEOUT) { // Pattern: Flash all pins for a cycle, // Then scan along pins for one cycle each i = i ? i << 1 : 1; gpio_put_all(i ? i : ~0); } gpio_set_dir_all_bits(0); printf("Wiggling halted.\n"); break; } case '\n': case '\r': break; case 'h': printhelp(); break; default: printf("\nUnrecognised command: %c\n", c); printhelp(); break; } } }

This firmware image was imported from the pico-examples repository. 


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