Yup, it's clearly labeled with the Hitachi name and the 44780 part number.

> -----Original Message-----
> From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On
> Behalf Of stef mientki
> Sent: Sunday, June 10, 2007 6:04 PM
> To: Microcontroller discussion list - Public.
> Subject: Re: [PIC] Interfacing to a Hitachi 44780 LCD in 4-bit mode
> 
> Matthew Mucker wrote:
> > 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.
> >
> Are you sure you have a "real" 44780 ?
> Anyway after using a lot of displays without any problems,
> I got a VARITRONIX type which gave a lots of trouble.
> An extra delay solved the problem, see code below.
> 
> success,
> Stef Mientki
> 
> 
> 
> |-- <Version: 1.2    ,01-09-2004, Stef Mientki
> --    - Extra delay in Init procedure, after 4-bits setting,
> --      needed for VARITRONIX MDLS-16268-series
> --        Problem was a uncomplete reset, after which the total
> behaviour was instable
> 
> ||
> const _HD44780_short_delay = 5|
> 
> |
> ||procedure LCD_init is
>   -- if multiplexed IO-pins, these values will be set just before
> sending
>   if ! HD44780_multiplexed_output then
>     HD44780_b4_pin        = low
>     HD44780_b5_pin        = low
>     HD44780_b6_pin        = low
>     HD44780_b7_pin        = low
>     HD44780_DataCmd_pin   = low
> 
>     HD44780_b4_direction  = output
>     HD44780_b5_direction  = output
>     HD44780_b6_direction  = output
>     HD44780_b7_direction  = output
>     HD44780_DataCmd_direction = output
>   end if
> 
>   HD44780_Enable_pin       = low
>   HD44780_Enable_direction = output
> 
>   delay_1mS ( 40 )                      -- even long enough for Vcc as
> low as 2.7V
>   HD44780_DataCmd_pin = low                 -- select command
>   _HD44780_write_low_nibble ( 0b_0011 ) -- first init
>   delay_1mS ( 5 )                       -- extra delay
>   _HD44780_write_low_nibble ( 0b_0011 ) -- second init
>   delay_10uS( 10 )                      -- extra delay
>   _HD44780_write_low_nibble ( 0b_0011 ) -- third init
> 
>   _HD44780_write_low_nibble ( 0b_0010 ) -- set 4-bit interface
>   delay_10uS( _HD44780_short_delay )    -- FOR SOME DISPLAYS
> (VARITRONIX) required delay
>   _HD44780_Command( 0b_0010_1000 )      -- two lines, 5x7 (high nibble)
>   _HD44780_Command( 0b_0000_1111 )      -- display on, cursor on, blink
> on
>   _HD44780_Command( 0b_0000_0001 )      -- clear display
>   _HD44780_Command( 0b_0000_0110 )      -- increment and no shift
> 
>   -- now display version of this lib
>   delay_1ms(100)
>   LCD_char_pos ( "V", 1)
>   LCD_char_pos ( " ", 2)
>   LCD_char_pos ( "1", 3)
>   LCD_char_pos ( ".", 4)
>   LCD_char_pos ( "4", 5)
> end procedure
> |
> 
> > 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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