635 with OS X 10.4


New member
So I've got my 635 recognized by my system (a 15" 1.67Ghz Powerbook running OS X 10.4.2) by using the driver from http://www.ftdichip.com/Drivers/FT232-FT245Drivers.htm

I grabbted the 635_linux.tar.gz code and it compiled cleanly, and it can connect to the LCD, but there seems to be some kind of communication issue because things don't work 100%.

basically after running:
./test635 /dev/tty.usbserial-3B1 115200

I get on the LCD:

Crystalfontz CFA-635
[logo] 20x4 + keypad &
[logo] LEDs in 51/4" bay
>>>This is line 4<<<

test635 spits out:

Ultra-simple CFA-635 command-line communications example.
Crystalfontz America, Inc. http://www.crystalfontz.com

./test635 PORT BAUD
PORT is something like "/dev/ttyS0" or "/dev/usb/ttyUSB0"
BAUD is 19200 or 115200
To clear the display, enter "clear" as an optional third parameter

Serial_Init:: success
"/dev/tty.usbserial-3B1" opened at "115200" baud.

Timed out waiting for a response.
Timed out waiting for a response.
Timed out waiting for a response.
Timed out waiting for a response.

Ctrl-C to exit.
Updated display, now waiting for packets

Any thoughts or suggestions?

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CF Web

Unfortunately we don't have a Mac here, which prevents us from being able to test the OS X operating system. We have, however, tested it thoroughly on Linux, so I'm confident it's not a bug in the code.

It seems as though you are getting at least some kind of communication between the OS and the display as the output of the display has the ">>>This is line 4<<<". What's confusing is that only line 4 made it out the display while the first 3 lines are still the default boot screen.

Even more confusing is the fact that you show 4 "timed out" responses (one for each line). Given that you have output on line 4, getting a timed out response doesn't make sense. What happens when you use the "clear" parameter? Does the display clear, does the program hang, etc?

Without a machine/OS to try and reproduce your issue, the best I can recommend is playing with the code a little to try and get a better feel for what's going on. Maybe set some flags in the sendpacket() or showrecievedpacket() functions to find out exactly where it's going wrong and manually debug the issue.

Good luck and please keep us posted if you have any success.
USB LCD Displays - Graphic and Character LCDs with a Keypad


New member
clear does nothing

I tried the 'clear' command and it doesn't do anything. I don't get any timeouts either. Maybe it's just some kind of timing thing... when I get some time, i'll play with the code and see if I can figure it out.