Re: New Driver: parallax

> 
> Hi everyone,
> 
> attached you will find a driver for Parallax serial displays:
> 
> 2 rows x 16 characters Non-backlit with Piezospeaker (#27976)
> 2 rows x 16 characters Backlit with Piezospeaker (#27977)
> 4 rows x 20 characters Backlit with Piezospeaker (#27979)
> 
> I wrote this driver some weeks ago on user's request, but didn't get any feedback if it works or not.
> 
> So if it happens that you own such a device, please give it a try.
> 
> The driver is still incomplete (misses documentation) and will not be committed for now until someone finds it is usable.
> 
> Regards,
> Markus
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Hi Markus,

I gave your driver a go with the latest from CVS. I'm running a 27977 off the motherboard COM1 header (ttyS0 in Ubuntu) with PIN3/5 through a simple circuit (NPN 2N3904 with 10K pull-up resistor on the RX line behind the NPN, and a 1K resistor ahead of the NPN base). I'm taking 5V off the floppy power lead from the PSU. Running Ubuntu 12.04 Server. Dips on the 27977 are set to on/on for 19200 baud. 

Your patch compiled and installed fine, I configured LCDd.conf w/: 
===============
[server]
Driver=parallax
...
[parallax]
Device=/dev/ttyS0
Speed=19200
Model=27977
Size=16x2
===============

When I started the daemon (ps shows parameters as "/usr/sbin/LCDd -s 1 -f -c /etc/LCDd.conf", I received "\"'s across the LCD display filling the matrix. I also received the following in syslog:

Jul  7 04:19:57 hostname LCDd: parallax: illegal Speed: 14; must be one of 2400, 9600, or 19200; using default 19200

Seems like a simple typo somewhere, but was unable to trace it down yet. Not sure if related to display issue.

Sending a character to /dev/ttyS0 via shell (echo -en '\x11' > /dev/ttyS0) several times causes an slash to appear as well. If I place the LCD in test mode (dips off/off), I receive the Parallax PacMan greeting (pretty cool).  

Can you think of anything obvious I'm missing? New to LCD's and serial I/O, but happy to test further. 

Thanks,

Jeremy