Re: [Lcd4linux-devel] new driver for graphic LCD on linux router

[Luis.F.Correia <Lui...@se...>]

Hi!

(sorry for top post, but it's hard to reply to HTML messages)

SPI is a bit different from I2C, you'll need to work a bit around it.
You may use our I2C driver as a reference, altough it was developed for the
HD44780.

Luis Correia

________________________________

	From: Bryan Kaminski [mailto:bka...@ii...] 
	Sent: Monday, April 28, 2008 5:19 PM
	To: Luis.F.Correia
	Cc: 'Michael Reinelt'; lcd...@li...
	Subject: Re: [Lcd4linux-devel] new driver for graphic LCD on linux
router
	
	
	Hey guys, 
	many thanks for the responses!
	I guess I should have been a little more detailed from the start. my
apologies. 

	I'm using a Buffalo router with OpenWRT on it. The buffalo has a
broadcom processor on it, which has a couple GPIO on it. The GPIO are
originally used to control LEDs for status, but I removed them and am using
the GPIO to control the LCD. The LCD uses 9-bit SPI data. The first bit
determines whether the following data is a "DATA" or "COMMAND" value. 
	http://www.sparkfun.com/commerce/product_info.php?products_id=569 
	 
	 

	Here is the datasheet:
	
http://www.sparkfun.com/datasheets/LCD/S1D15G10D08BE_TM_MF1493_03.pdf


	I coded up a very basic kernel driver and hacked a test program out.
	http://www.youtube.com/watch?v=Xjdy9p-VSow

	Also, I think this display is supported by serdisplib (i know there
is a plugin), but again, not for a custom SPI interface (as far as i can
tell). 
	I want to use lcd4linux so i dont have to reinvent the wheel and
recode character drivers and widgets and etc etc, when its all been done so
nicely already :)

	So to summarize,
	I'm controlling the SPI LCD from the GPIO on the target hardware
processor using a basic kernel character driver. I'm wondering how to get
this to work with lcd4linux.  
	I haven't looked at the I2C sources yet, but I'm assuming they use
some kind of onboard I2C chip or interface already located on the
motherboard. 

	I'll check them out anyways to take a look.
	Thanks for reading and any heads-up on this. 

	On Apr 28, 2008, at 3:05 AM, Luis.F.Correia wrote:


		Hi! 


			-----Original Message-----
			From: lcd...@li... 
	
[mailto:lcd...@li...] On 
			Behalf Of Michael Reinelt
			Sent: Monday, April 21, 2008 8:35 AM
			To: Bryan Kaminski
			Cc: lcd...@li...
			Subject: Re: [Lcd4linux-devel] new driver for
graphic LCD on 
			linux router

			Hi Bryan,


				i coded up a really basic linux character
driver for a Nokia color 
				graphic LCD (tested and working)

			Sounds interesting!


				But the thing is, its controlled by the
processor's GPIO ports,not  
				RS232 or parallel. I'm not sure how to write
a driver for 

			lcd4linux  

				that would access these pins.

			Have you got some more information about the device?
Is the display a
			standalone display with a i2c interface, or is it
something like a
			complete "embedded system"?

			There are some i2c drivers available, just grep the
sources 
			to get some
			hints. There are several guys here who are working
with i2c (I am not)


		I am :)

		When you talk about the processor GPIO, are you referring to
the processor
		on the LCD display itself, or the intended linux hardware?

		Please give us more detail, I2C is a valid option, I'm using
a display
		from an HP printer in I2C mode without major problems so
far.

		Luis Correia