Initial commit

1 files changed, 128 insertions, 0 deletions

diff --git a/main/main.c b/main/main.c
new file mode 100644
index 0000000..5ffcb6d
--- /dev/null
+++ b/main/main.c
@@ -0,0 +1,128 @@
+#include <stdio.h>
+#include <string.h>
+
+#include "driver/spi_master.h"
+#include "driver/gpio.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "atascii.h"
+#include "esp_log.h"
+
+
+#define NUM_COL              160
+#define NUM_ROW              8
+#define CHAR_HEIGHT          8
+#define CHAR_WIDTH           8
+#define RED                  1
+#define GREEN                2
+#define ORANGE               3
+
+#define PIN_NUM_MISO         12
+#define PIN_NUM_MOSI         13
+#define PIN_NUM_CLK          14
+#define PIN_NUM_CS           15
+#define PIN_NUM_R_LATCH      16
+#define PIN_NUM_R_CLK        17
+#define PIN_NUM_R_ADDR_0     5
+#define PIN_NUM_R_ADDR_1     18
+#define PIN_NUM_R_ADDR_2     19
+
+#define TAG           "led_display"
+
+static uint16_t pattern[NUM_ROW][NUM_COL / 8]; // each column is two bits, so 8 can fit in 16-bit integer
+
+void draw_char_at_position(char character, uint16_t col_start, uint16_t row_start, uint16_t color) {
+    uint8_t cur_char_row;
+    for(int row = row_start; (row - row_start) < CHAR_HEIGHT && row < NUM_ROW; row++) {
+        cur_char_row = atascii_font[(uint8_t) character][row - row_start];
+        for(int col = col_start; (col - col_start) < CHAR_WIDTH && col < NUM_COL; col++) {
+            pattern[row][col / 8] = (pattern[row][col / 8] & ~(0b0000000000000011 << (2 * (col - col_start)))); // clear this column (note the bitwise inversion)
+            if((1 << (col - col_start)) & cur_char_row) {
+                pattern[row][col / 8] = ((pattern[row][col / 8]) | color << (2 * (col - col_start))); // write color to column
+            }
+        }
+    }
+}
+
+void app_main(void)
+{
+    esp_err_t ret;
+    spi_device_handle_t spi;
+
+    spi_bus_config_t buscfg={
+        .miso_io_num=PIN_NUM_MISO,
+        .mosi_io_num=PIN_NUM_MOSI,
+        .sclk_io_num=PIN_NUM_CLK,
+        .quadwp_io_num=-1,
+        .quadhd_io_num=-1,
+        .max_transfer_sz=3*600*2*8,
+        .flags=SPICOMMON_BUSFLAG_DUAL
+    };
+
+    spi_device_interface_config_t devcfg={
+        .clock_speed_hz=1*1000*1000,            //Clock out at 1 MHz
+        .mode=0,                                //SPI mode 0
+        .spics_io_num=PIN_NUM_CS,               //CS pin
+        .queue_size=7,                          //We want to be able to queue 7 transactions at a time
+        .flags=SPI_DEVICE_HALFDUPLEX,           //Needed to use both data lines for output
+    };
+
+    //Initialize the SPI bus and attach our device handle
+    ret=spi_bus_initialize(HSPI_HOST, &buscfg, SPI_DMA_CH_AUTO);
+    ESP_ERROR_CHECK(ret);
+    ret=spi_bus_add_device(HSPI_HOST, &devcfg, &spi);
+    ESP_ERROR_CHECK(ret);
+
+    ESP_LOGI(TAG, "Initialized SPI host.");
+
+    gpio_set_direction(PIN_NUM_R_LATCH, GPIO_MODE_OUTPUT);
+    gpio_set_direction(PIN_NUM_R_CLK, GPIO_MODE_OUTPUT);
+    gpio_set_direction(PIN_NUM_R_ADDR_0, GPIO_MODE_OUTPUT);
+    gpio_set_direction(PIN_NUM_R_ADDR_1, GPIO_MODE_OUTPUT);
+    gpio_set_direction(PIN_NUM_R_ADDR_2, GPIO_MODE_OUTPUT);
+
+    ESP_LOGI(TAG, "Setup GPIO.");
+
+    char* text = "Hello World!! 1234567890";
+    for(int i = 0; i < strlen(text); i++) {
+        draw_char_at_position(text[i], i * CHAR_WIDTH, 0, RED);
+    }
+
+    ESP_LOG_BUFFER_HEX(TAG, pattern[0], 16);
+    ESP_LOG_BUFFER_HEX(TAG, pattern[1], 16);
+    ESP_LOG_BUFFER_HEX(TAG, pattern[2], 16);
+    ESP_LOG_BUFFER_HEX(TAG, pattern[3], 16);
+    ESP_LOG_BUFFER_HEX(TAG, pattern[4], 16);
+    ESP_LOG_BUFFER_HEX(TAG, pattern[5], 16);
+    ESP_LOG_BUFFER_HEX(TAG, pattern[6], 16);
+    ESP_LOG_BUFFER_HEX(TAG, pattern[7], 16);
+
+    ESP_LOGI(TAG, "Done drawing pattern.");
+
+    uint8_t current_row = 0;
+    while(true) {
+        spi_transaction_t t;
+        memset(&t, 0, sizeof(t));
+        t.length = NUM_COL;
+        t.tx_buffer = pattern[current_row];
+        t.flags = SPI_TRANS_MODE_DIO;  // output on two data lines. Even bits go to GREEN, odd to RED
+        ret = spi_device_polling_transmit(spi, &t);
+        ESP_ERROR_CHECK(ret);
+
+        gpio_set_level(PIN_NUM_R_LATCH, 0);
+        gpio_set_level(PIN_NUM_R_CLK, 1);
+
+        gpio_set_level(PIN_NUM_R_ADDR_0, 1 & current_row);
+        gpio_set_level(PIN_NUM_R_ADDR_1, 1 & (current_row >> 1));
+        gpio_set_level(PIN_NUM_R_ADDR_2, 1 & (current_row >> 2));
+
+        gpio_set_level(PIN_NUM_R_LATCH, 1);
+        gpio_set_level(PIN_NUM_R_CLK, 0);
+
+        if(++current_row == NUM_ROW) {
+            current_row = 0;
+        }
+
+        vTaskDelay((10) / portTICK_PERIOD_MS);
+    }
+}