lcd4linux-devel

[Lcd4linux-devel] I2C display (one more time)

[Paul K. <pau...@xs...>]

Hi everyone,

Finally found the time to have a look at the I2C display. Let's start 
with the good news:

I HAVE GOT IT WORKING!!!! :-)

Turned out there where several issues. Some of them are in the parallel 
port part too. So that is a bit weird.

On of the things that surprised me was that the commands where send 
using the send_byte command that actually tried to set the RS signal. 
(which should only be done for data) This is the strange thing. parallel 
port code does the same. I guess it has to do with the copy of the 
source code that I got from the web-site.

The second problem was that the SIGNAL_ENABLE, SIGNAL_RS and SIGNAL_RW 
were never set correctly. I did it manually now. But how should it be done?

And that's it! Good work Luis! You were nearly there!
So, if anyone can tell me what I should do to get this stuff in the 
official code?

cheers,

Paul

Re: [Lcd4linux-devel] I2C display (one more time)

[Luis C. <lfc...@lf...>]

Paul Kamphuis wrote:

> Hi everyone,
>
> Finally found the time to have a look at the I2C display. Let's start 
> with the good news:
>
> I HAVE GOT IT WORKING!!!! :-)
>
> Turned out there where several issues. Some of them are in the 
> parallel port part too. So that is a bit weird.
>
> On of the things that surprised me was that the commands where send 
> using the send_byte command that actually tried to set the RS signal. 
> (which should only be done for data) This is the strange thing. 
> parallel port code does the same. I guess it has to do with the copy 
> of the source code that I got from the web-site.
>
> The second problem was that the SIGNAL_ENABLE, SIGNAL_RS and SIGNAL_RW 
> were never set correctly. I did it manually now. But how should it be 
> done?
>
> And that's it! Good work Luis! You were nearly there!
> So, if anyone can tell me what I should do to get this stuff in the 
> official code?
>
> cheers,
>
> Paul


Send me the code you've got in a private mail, so that I can take a good 
look at it.
Maybe I can commit it if it looks good enough.

cheers!

Luis

Re: [Lcd4linux-devel] I2C display (one more time)

[Michael R. <re...@eu...>]

Hi Paul,

> I HAVE GOT IT WORKING!!!! :-)
Well, thats good news, indeed!

> On of the things that surprised me was that the commands where send
> using the send_byte command that actually tried to set the RS signal.
> (which should only be done for data) This is the strange thing. parallel
> port code does the same. I guess it has to do with the copy of the
> source code that I got from the web-site.

I double-checked the data sheet, and it looks like there was a mistake
in the Wiki documentation:

The data sheet I got says: RS = Register select, low => instruction
(command), high => data

So the parport code seems to be correct (it must be correct, because
it's working. And always remember: If it works, don't fix it :-)

> The second problem was that the SIGNAL_ENABLE, SIGNAL_RS and SIGNAL_RW
> were never set correctly. I did it manually now. But how should it be done?
These variables are set by a call to drv_generic_parport_wire_ctrl().
There is no such function for I2C. Maybe you should write one. Take a
look at drv_generic_parport.c; maybe there should be a drv_generic_i2c.c
too.

> So, if anyone can tell me what I should do to get this stuff in the
> official code?
As Luis already wrote, send the code to him, he can commit it into CVS.
If you did change something in the parport part, too, I wanna have a
look, too, please!

For the future, I can give you CVS write access, so you can commit
further changes yourself. All I'd need is your SourceForge account name.


bye, Michael

-- 
Michael Reinelt <re...@eu...>
http://home.pages.at/reinelt
GPG-Key 0xDF13BA50
ICQ #288386781