Merge pull request #7 from kholia/better-init-for-displays

Add more robust init for 16x2 I2C LCD displays

Examples/HAL/I2C/PCF8574_I2C_LCD_F003_SOP16/LCD1602.c

@@ -0,0 +1,102 @@
+#include "LCD1602.h"
+
+uint8_t portLcd = 0;
+
+static void LCD_WriteByte(uint8_t bt) {
+  HAL_I2C_Master_Transmit(&LCD_I2C, ADRESS_I2C_LCD, &bt, 1, 1000);
+}
+
+static void LCD_SendCmd_8bit(uint8_t bt) {
+  LCD_WriteByte(portLcd |= 0x04);
+  HAL_Delay(1);
+  LCD_WriteByte(portLcd | bt);
+  LCD_WriteByte(portLcd &= ~ 0x04);
+  HAL_Delay(1);
+}
+
+static void LCD_SendCmd(uint8_t bt) {
+  bt <<= 4;
+  LCD_SendCmd_8bit(bt);
+}
+
+static void LCD_SendByte(uint8_t bt, uint8_t mode) {
+  if (mode == 0) {
+    LCD_WriteByte(portLcd &= ~ 0x01); // RS = 0;
+  }
+  else {
+    LCD_WriteByte(portLcd |= 0x01); // RS = 1;
+  }
+
+  uint8_t tempBuf = 0;
+  tempBuf = bt >> 4;
+
+  LCD_SendCmd(tempBuf);
+  LCD_SendCmd(bt);
+}
+
+void LCD_Init(void) {
+  HAL_Delay(50);
+  LCD_SendCmd(0x03);
+  HAL_Delay(5);
+  LCD_SendCmd(0x03);
+  HAL_Delay(1);
+  LCD_SendCmd(0x03);
+  HAL_Delay(10);
+
+  LCD_SendCmd(0x02); // 0x02 // 4bit mode
+  HAL_Delay(2);
+
+  LCD_SendByte(0x38, 0);
+  HAL_Delay(2);
+
+  LCD_SendByte(0x02, 0);
+  HAL_Delay(2);
+  LCD_SendByte(0x0C, 0);
+  HAL_Delay(2);
+  LCD_SendByte(0x01, 0);
+  HAL_Delay(2);
+  LCD_SendByte(0x06, 0);
+  HAL_Delay(1);
+  //---------------------------------------------------------------------------------
+
+  LCD_WriteByte(portLcd |= 0x08);
+  LCD_WriteByte (portLcd &= ~ 0x02);
+}
+
+void LCD_PrintString(char* str) {
+  uint8_t i = 0;
+
+  while (str[i] != 0) {
+    LCD_SendByte(str[i], 1);
+    i++;
+  }
+}
+
+void LCD_Clear(void) {
+
+  LCD_SendByte(0x01, 0);
+  HAL_Delay(2);
+}
+
+void LCD_SetCursor(uint8_t x, uint8_t y) {
+  switch (y) {
+    case 0:
+      LCD_SendByte(x | 0x80, 0);
+      HAL_Delay(1);
+      break;
+    case 1:
+      LCD_SendByte(( 0x40 + x) | 0x80, 0);
+      HAL_Delay(1);
+      break;
+    case 2:
+      LCD_SendByte(( 0x14 + x) | 0x80, 0);
+      HAL_Delay(1);
+      break;
+    case 3:
+      LCD_SendByte(( 0x54 + x) | 0x80, 0);
+      HAL_Delay(1);
+      break;
+    default:
+      break;
+  }
+}

Examples/HAL/I2C/PCF8574_I2C_LCD_F003_SOP16/LCD1602.h

@@ -0,0 +1,34 @@
+#ifndef _LCD1602_H
+#define _LCD1602_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+#include "py32f0xx_hal.h"
+#include "py32f0xx_hal_i2c.h"
+
+#include "main.h"
+#include "LCD1602_config.h"
+
+extern uint8_t portLcd;
+
+#ifdef LCD1602_I2C
+extern I2C_HandleTypeDef I2cHandle;
+#endif
+
+void LCD_Init(void);
+
+void LCD_PrintString( char* str );
+
+void LCD_Clear(void);
+
+void LCD_SetCursor( uint8_t x, uint8_t y );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

Examples/HAL/I2C/PCF8574_I2C_LCD_F003_SOP16/LCD1602_config.h

@@ -0,0 +1,23 @@
+#ifndef _LCD1602_CONFIG_H
+#define _LCD1602_CONFIG_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "main.h"
+
+#define LCD1602_I2C
+
+#if defined (LCD1602_I2C)
+
+#define LCD_I2C        I2cHandle
+#define ADRESS_I2C_LCD (0x27 << 1) //  (0x27 << 1)  (0x3F << 1)
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

Examples/HAL/I2C/PCF8574_I2C_LCD_F003_SOP16/main.c

@@ -4,93 +4,30 @@
 #include "py32f0xx_hal_i2c.h"
 #include "py32f0xx_bsp_printf.h"
 
-#define I2C_ADDRESS        0xA0     /* host address */
+#include "LCD1602.h"
+
+#define I2C_ADDRESS 0xA0 // host address
 
 I2C_HandleTypeDef I2cHandle;
 
 void APP_ErrorHandler(void);
 static void APP_I2C_Config(void);
 
-#define SLAVE_ADDRESS_LCD 0x4E // PCF8574
+int SLAVE_ADDRESS_LCD = 0; // PCF8574
 
-// LCD handling functions are borrowed from https://controllerstech.com/i2c-lcd-in-stm32/
-void lcd_send_cmd (char cmd)
-{
-  char data_u, data_l;
-  uint8_t data_t[4];
-  data_u = (cmd&0xf0);
-  data_l = ((cmd<<4)&0xf0);
-  data_t[0] = data_u|0x0C; // en=1, rs=0
-  data_t[1] = data_u|0x08; // en=0, rs=0
-  data_t[2] = data_l|0x0C; // en=1, rs=0
-  data_t[3] = data_l|0x08; // en=0, rs=0
-  HAL_I2C_Master_Transmit (&I2cHandle, SLAVE_ADDRESS_LCD,(uint8_t *) data_t, 4, 100);
-}
+int find_lcd_i2c_address() {
+  int ret = -1;
 
-void lcd_send_data (char data)
-{
-  char data_u, data_l;
-  uint8_t data_t[4];
-  data_u = (data&0xf0);
-  data_l = ((data<<4)&0xf0);
-  data_t[0] = data_u|0x0D; // en=1, rs=0
-  data_t[1] = data_u|0x09; // en=0, rs=0
-  data_t[2] = data_l|0x0D; // en=1, rs=0
-  data_t[3] = data_l|0x09; // en=0, rs=0
-  HAL_I2C_Master_Transmit (&I2cHandle, SLAVE_ADDRESS_LCD,(uint8_t *) data_t, 4, 100);
-}
-
-void lcd_clear (void)
-{
-  lcd_send_cmd (0x80);
-  for (int i=0; i<70; i++) {
-    lcd_send_data (' ');
-  }
-}
-
-void lcd_put_cur(int row, int col)
-{
-    switch (row) {
-        case 0:
-            col |= 0x80;
-            break;
-        case 1:
-            col |= 0xC0;
-            break;
+  for (int i = 1; i < 128; i++) {
+    ret = HAL_I2C_IsDeviceReady(&I2cHandle, (uint16_t)(i << 1), 3, 1000);
+    if (ret != HAL_OK) {
     }
+    else if (ret == HAL_OK) {
+      return i;
+    }
+  }
 
-    lcd_send_cmd (col);
-}
-
-void lcd_init (void)
-{
-  // 4 bit initialisation
-  HAL_Delay(50); // wait for > 40ms
-  lcd_send_cmd (0x30);
-  HAL_Delay(5); // wait for > 4.1ms
-  lcd_send_cmd (0x30);
-  HAL_Delay(1); // wait for > 100us
-  lcd_send_cmd (0x30);
-  HAL_Delay(10);
-  lcd_send_cmd (0x20); // 4bit mode
-  HAL_Delay(10);
-
-  // display initialisation
-  lcd_send_cmd (0x28); // Function set --> DL=0 (4 bit mode), N = 1 (2 line display) F = 0 (5x8 characters)
-  HAL_Delay(1);
-  lcd_send_cmd (0x08); // Display on/off control --> D=0, C=0, B=0 ---> display off
-  HAL_Delay(1);
-  lcd_send_cmd (0x01); // clear display
-  HAL_Delay(1);
-  HAL_Delay(1);
-  lcd_send_cmd (0x06); // Entry mode set --> I/D = 1 (increment cursor) & S = 0 (no shift)
-  HAL_Delay(1);
-  lcd_send_cmd (0x0C); // Display on/off control --> D = 1, C and B = 0. (Cursor and blink, last two bits)
-}
-
-void lcd_send_string (char *str)
-{
-  while (*str) lcd_send_data (*str++);
+  return -1;
 }
 
 int main(void)
@@ -102,12 +39,15 @@ int main(void)
 
   APP_I2C_Config();
 
-  lcd_init ();
+  SLAVE_ADDRESS_LCD = find_lcd_i2c_address();
+  SLAVE_ADDRESS_LCD = (SLAVE_ADDRESS_LCD << 1);
 
-  lcd_send_string ("HELLO WORLD!");
+  LCD_Init();
+  LCD_SetCursor(0, 0);
+  LCD_PrintString("HELLO WORLD!");
   HAL_Delay(1000);
-  lcd_put_cur(1, 0);
-  lcd_send_string("HOWDY!");
+  LCD_SetCursor(0, 1);
+  LCD_PrintString("HOWDY!");
   HAL_Delay(2000);
 
   while(1);

Examples/HAL/I2C/PCF8574_I2C_LCD_F003_SOP16/main.h

@@ -0,0 +1,29 @@
+// Copyright 2021 IOsetting <iosetting(at)outlook.com>
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef __MAIN_H
+#define __MAIN_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void APP_ErrorHandler(void);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __MAIN_H */