PICAXE BASIC routines for control LCD 1602.

Set of PICAXE BASIC routines for control classic LCD 1602 with HD44780 driver.

Motivation

There is some introduction how to use LCDs with HD44780 driver in the official manual picaxe_manual3 (page 31). But example program is incomprehensible - it is basically a bunch of magical numbers. Therefore I decided to study HD44780 datasheet and write my own routines.

Alternative LCDs

• oficial AXE033 SERIAL/I2C LCD
  • easy to use; a bit expensive; also not widely available like LCD 1602 with HD44780
• LCD 1602 with I2C interface

Routines

There is the support of 4-bit mode and LCD with one or two lines.

See source code and example programs.

Feel free to modify routines as you need, to add new routines, to remove bugs :)

Tested only with PICAXE 20M2

for programmer

• lcd_4bm_init
• lcd_init_custom_symbols
• lcd_4bm_send_char
• lcd_clear
• lcd_move_to_col_at_first_line
• lcd_move_to_col_at_second_line
• lcd_move_to_left
• lcd_move_to_right

for inner use (primarily, but not exclusively)

• lcd_4bm_send_cmd
• lcd_4bm_send
• lcd_pulse_E
• lcd_lsb_to_Dx_pins
• lcd_Msb_to_Dx_pins

Circuit diagram for the 4-bit mode