lcd1602

/*
 * LCD1602.c
 *
 *  Created on: Jan 22, 2023
 *      Author: Psi
 */

#include "LCD1602.h"

#define LCD_ADDR (0x27 << 1)

#define PIN_RS    (1 << 0)
#define PIN_EN    (1 << 2)
#define BACKLIGHT (1 << 3)

#define LCD_DELAY_MS 5

void I2C_Scan(I2C_HandleTypeDef *hi2c) {
    HAL_StatusTypeDef res;

    for(uint16_t i = 0; i < 128; i++) {
        res = HAL_I2C_IsDeviceReady(hi2c, i << 1, 1, 10);

        if(res == HAL_OK) {
            HAL_GPIO_TogglePin(GPIOC, GPIO_PIN_13);
        } else {
        }
    }
}

HAL_StatusTypeDef LCD_SendInternal(I2C_HandleTypeDef *hi2c, uint8_t lcd_addr, uint8_t data, uint8_t flags) {
    HAL_StatusTypeDef res;
    for(;;) {
        res = HAL_I2C_IsDeviceReady(hi2c, lcd_addr, 1, HAL_MAX_DELAY);
        if(res == HAL_OK)
            break;
    }

    uint8_t up = data & 0xF0;
    uint8_t lo = (data << 4) & 0xF0;

    uint8_t data_arr[4];
    data_arr[0] = up|flags|BACKLIGHT|PIN_EN;
    data_arr[1] = up|flags|BACKLIGHT;
    data_arr[2] = lo|flags|BACKLIGHT|PIN_EN;
    data_arr[3] = lo|flags|BACKLIGHT;

    res = HAL_I2C_Master_Transmit(hi2c, lcd_addr, data_arr, sizeof(data_arr), HAL_MAX_DELAY);
    HAL_Delay(LCD_DELAY_MS);
    return res;
}

void LCD_SendCommand(I2C_HandleTypeDef *hi2c, uint8_t lcd_addr, uint8_t cmd) {
    LCD_SendInternal(hi2c, lcd_addr, cmd, 0);
}

void LCD_SendData(I2C_HandleTypeDef *hi2c, uint8_t lcd_addr, uint8_t data) {
    LCD_SendInternal(hi2c, lcd_addr, data, PIN_RS);
}

void LCD_Init(I2C_HandleTypeDef *hi2c, uint8_t lcd_addr) {
    // 4-bit mode, 2 lines, 5x7 format
    LCD_SendCommand(hi2c, lcd_addr, 0b00110000);
    // display & cursor home (keep this!)
    LCD_SendCommand(hi2c, lcd_addr, 0b00000010);
    // display on, right shift, underline off, blink off
    LCD_SendCommand(hi2c, lcd_addr, 0b00001100);
    // clear display (optional here)
    LCD_SendCommand(hi2c, lcd_addr, 0b00000001);
}

void LCD_SendString(I2C_HandleTypeDef *hi2c, uint8_t lcd_addr, char *str) {
    while(*str) {
        LCD_SendData(hi2c, lcd_addr, (uint8_t)(*str));
        str++;
    }
}

void init(I2C_HandleTypeDef *hi2c, uint8_t lcd_addr) {
    I2C_Scan(hi2c);
    LCD_Init(hi2c, lcd_addr);

    // set address to 0x00
    LCD_SendCommand(hi2c, lcd_addr, 0b10000000);
    LCD_SendString(hi2c, lcd_addr, " Using 1602 LCD");

    // set address to 0x40
    LCD_SendCommand(hi2c, lcd_addr, 0b11000000);
    LCD_SendString(hi2c, lcd_addr, "  over I2C bus");
}