/** * Copyright (c) 2020 Raspberry Pi (Trading) Ltd. * * SPDX-License-Identifier: BSD-3-Clause */ #include #include #include #include #include #include #include "pico/stdlib.h" #include "hardware/pwm.h" #include "hardware/i2c.h" #define PI 3.14159265358979323433 #define STEPS_PER_SECOND 100 #define STEP_SLEEP_DURATION (1000 / STEPS_PER_SECOND) #define EXTERNAL_LED_PIN 22 #define SSD1306_I2C_SDA_PIN 12 #define SSD1306_I2C_SCL_PIN 13 #define SSD1306_I2C_ADDRESS 0x3C #define SSD1306_I2C_BAUDRATE 1000000 #define SSD1306_WIDTH 128 #define SSD1306_HEIGHT 64 #define SSD1306_FRAME_SIZE (SSD1306_WIDTH * SSD1306_HEIGHT / 8) static uint8_t ssd1306_framebuffer[SSD1306_WIDTH * SSD1306_HEIGHT / 8] = {0}; void setupUART(){ uart_inst_t * UART_ID = uart0; const uint BAUD = 115200; const uint TX_PIN = 0; const uint RX_PIN = 1; uart_init(UART_ID, BAUD); stdio_uart_init_full(UART_ID, BAUD, TX_PIN, RX_PIN); gpio_set_function(TX_PIN, GPIO_FUNC_UART); gpio_set_function(RX_PIN, GPIO_FUNC_UART); uart_set_format(UART_ID, 8, 1, UART_PARITY_NONE); } void ssd1306_write_command(i2c_inst_t *i2c_port, uint8_t command) { uint8_t buf[2] = {0x00, command}; int ret = i2c_write_blocking(i2c_port, SSD1306_I2C_ADDRESS, buf, 2, false); if(ret != 2) printf("write command failed"); } void ssd1306_init(i2c_inst_t *i2c_port) { ssd1306_write_command(i2c_port, 0xAE); // Display OFF ssd1306_write_command(i2c_port, 0x20); // Set Memory Addressing Mode ssd1306_write_command(i2c_port, 0x00); // Horizontal addressing mode ssd1306_write_command(i2c_port, 0xB0); // Page start address ssd1306_write_command(i2c_port, 0xC8); // COM Output Scan Direction ssd1306_write_command(i2c_port, 0x00); // Low column address ssd1306_write_command(i2c_port, 0x10); // High column address ssd1306_write_command(i2c_port, 0x40); // Start line address ssd1306_write_command(i2c_port, 0x81); // Contrast control ssd1306_write_command(i2c_port, 0xFF); // Max contrast ssd1306_write_command(i2c_port, 0xA1); // Segment remap ssd1306_write_command(i2c_port, 0xA6); // Normal display ssd1306_write_command(i2c_port, 0xA8); // Multiplex ratio ssd1306_write_command(i2c_port, 0x3F); // Duty = 1/64 ssd1306_write_command(i2c_port, 0xA4); // Display follows RAM ssd1306_write_command(i2c_port, 0xD3); // Display offset ssd1306_write_command(i2c_port, 0x00); // No offset ssd1306_write_command(i2c_port, 0xD5); // Display clock ssd1306_write_command(i2c_port, 0xF0); ssd1306_write_command(i2c_port, 0xD9); // Pre-charge period ssd1306_write_command(i2c_port, 0x22); ssd1306_write_command(i2c_port, 0xDA); // COM pins ssd1306_write_command(i2c_port, 0x12); ssd1306_write_command(i2c_port, 0xDB); // VCOMH deselect level ssd1306_write_command(i2c_port, 0x20); ssd1306_write_command(i2c_port, 0x8D); // Charge pump ssd1306_write_command(i2c_port, 0x14); ssd1306_write_command(i2c_port, 0xAF); // Display ON } void ssd1306_flush(i2c_inst_t *i2c_port, uint8_t* data, uint data_len) { // Set column address range: 0 to 127 ssd1306_write_command(i2c_port, 0x21); // Set column address command ssd1306_write_command(i2c_port, 0x00); // Start column ssd1306_write_command(i2c_port, 0x7F); // End column (127) // Set page address range: 0 to 7 ssd1306_write_command(i2c_port, 0x22); // Set page address command ssd1306_write_command(i2c_port, 0x00); // Start page ssd1306_write_command(i2c_port, 0x07); // End page (7) // Start I2C transaction to send full framebuffer uint8_t tx[1 + data_len]; tx[0] = 0x40; memcpy(tx+1, ssd1306_framebuffer, data_len); int ret = i2c_write_blocking(i2c_port, SSD1306_I2C_ADDRESS, tx, sizeof(tx), false); } void ssd1306_flush_region(i2c_inst_t *i2c_port, uint8_t* data, uint data_len) { uint8_t col_start = 0; uint8_t col_end = 63; uint8_t page_start = 0; uint8_t page_end = 3; const uint width = (uint)(col_end - col_start + 1); const uint pages = (uint)(page_end - page_start + 1); uint8_t tx[1 + width * pages]; tx[0] = 0x40; for(int i = 0; i < pages; i++){ memcpy(tx + 1 + i * width, data + SSD1306_WIDTH * i + col_start, width); } // Set column address range: 0 to 127 ssd1306_write_command(i2c_port, 0x21); // Set column address command ssd1306_write_command(i2c_port, col_start); // Start column ssd1306_write_command(i2c_port, col_end); // End column (127) // Set page address range: 0 to 7 ssd1306_write_command(i2c_port, 0x22); // Set page address command ssd1306_write_command(i2c_port, page_start); // Start page ssd1306_write_command(i2c_port, page_end); // End page (7) // Start I2C transaction to send full framebuffer int ret = i2c_write_blocking(i2c_port, SSD1306_I2C_ADDRESS, tx, sizeof(tx), false); } void ssd1306_setpixel(uint8_t x, uint8_t y, bool value){ int page = y / 8; int bit_offset = y % 8; int byte_idx = page * SSD1306_WIDTH + x; ssd1306_framebuffer[byte_idx] &= ~(1 << bit_offset); ssd1306_framebuffer[byte_idx] |= value << bit_offset; } int main() { setupUART(); i2c_inst_t * I2C_ID = i2c0; i2c_init(I2C_ID, SSD1306_I2C_BAUDRATE); gpio_set_function(SSD1306_I2C_SDA_PIN, GPIO_FUNC_I2C); gpio_set_function(SSD1306_I2C_SCL_PIN, GPIO_FUNC_I2C); gpio_pull_up(SSD1306_I2C_SDA_PIN); gpio_pull_up(SSD1306_I2C_SCL_PIN); sleep_ms(100); ssd1306_init(I2C_ID); memset(ssd1306_framebuffer, 0x00, SSD1306_FRAME_SIZE); ssd1306_flush(I2C_ID, ssd1306_framebuffer, SSD1306_FRAME_SIZE); printf("ssd1306 setup\n"); sleep_ms(100); const int SAMPLE_FRAMES = 100; uint32_t start_ms = to_ms_since_boot(get_absolute_time()); for (int i = 0; i < SAMPLE_FRAMES; ++i) { memset(ssd1306_framebuffer, 0x00, SSD1306_FRAME_SIZE); ssd1306_flush(I2C_ID, ssd1306_framebuffer, SSD1306_FRAME_SIZE); memset(ssd1306_framebuffer, 0xFF, SSD1306_FRAME_SIZE); ssd1306_flush(I2C_ID, ssd1306_framebuffer, SSD1306_FRAME_SIZE); } uint32_t end_ms = to_ms_since_boot(get_absolute_time()); uint32_t elapsed_ms = end_ms - start_ms; float frames = (float)SAMPLE_FRAMES * 2.0f; // two frames per loop iteration float fps = frames * 1000.0f / (float)elapsed_ms; printf("Elapsed: %u ms for %.0f frames -> FPS = %.2f\n", elapsed_ms, frames, fps); memset(ssd1306_framebuffer, 0x0, SSD1306_FRAME_SIZE); ssd1306_flush(I2C_ID, ssd1306_framebuffer, SSD1306_FRAME_SIZE); while (true) tight_loop_contents(); }