All,

I've been debugging this problem for weeks and haven't found where my error
is, so I'm turning to the list for help. I'm trying to drive a Hitachi 44780
LCD module in 4-bit mode from a PIC chip.

I have my PIC 16F628 connected to the LCD module as follows:

RB4 --> LCD_E
RB3 --> LCD_RS
RA0 --> LCD_D4
RA1 --> LCD_D5
RA2 --> LCD_D6
RA3 --> LCD_D7

I have tested each of these outputs and verified that I can write a logic
'1' or '0' and get the expected voltage.

I've used Myke Predko's page (www.myke.com/lcd.htm) as my main reference.

According to MPLAB SIM, my code is writing the following when the LCD_E line
is blipped:

			LCD
			DATA	LCD
TIME			7654	RS	notes

0			0011	0	send 0x03, wait 5msec
5.1964		0011	0	send 0x03, wait 160 usec
5.5218		0011	0	send 0x03 a third time, wait 160 usec
5.8472		0010	0	Enable 4-bit mode (following commands are
two nybbles)
6.0126		0010	0
6.1766		1000	0	00101000: 4-bit mode, 2 line display, 5x7
font
6.3248		0000	0
6.5068		1000	0	00001000: disp. Off, cursor off, blink off
6.6730		0000	0
6.8370		0001	0	00000001: clear display, wait
12.0356		0000	0
12.1996		0110	0	00000110: increment cursor/no shift
12.3658		0000	0
12.5298		1100	0	00001100: display on, cursor off, blink off
12.6968		0000	0	
12.8608		0010	0	00000010: home cursor
18.0618		0101	1
18.2258		0111	1	Letter 'W', first character to be displayed

The LCD doesn't seem to initialize and for sure my characters aren't being
displayed. I'm getting quite frustrated with this project. I'm hoping
someone out there can spot the error of my ways for me and help me get back
on the straight and narrow.

Thanks,

-Matt

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