I've been playing around with a serial 633 that I've hooked up via a USB to Serial converter. Using the linux example program, I'm getting some rather strange results: the LCD changes as it's supposed to (The text on the screen changes to say 'this is line 1', 'this is line 2'. If the "clear" parameter is given, the screen clears instead), but the output I get to my terminal is:
Now, my natural first inclination is that the connection is bad or I've otherwise screwed up my wiring, but here's the *really* weird part:
Just on a lark, I tried "cat /dev/ttyUSB0" and pressed a button. Out popped an 8 byte sequence: 40 80 f8 71 40 80 9d d0, and it consistently produced similar sequences of bytes whenever I pressed a key. Next, I tried catting ttyUSB0 while the example program was running, and again, it was producing output. All this says to me that, yes, the LCD is sending response packets, but something in the software is failing to capture them.
My guess is that this might be some sort of version difference in how the serial interface works. Has anyone run into this or have a solution?
My setup:
Crystalfontz 633 HW 1.3 FW 1.5, connected using USB to serial converter on /dev/ttyUSB0
Ubuntu Intrepid Ibex (8.10), linux 2.6.27-11-generic
It never reports receiving any packets back from the LCD, so I can't do things like read button presses. lcd4linux similarly goes into paroxisms because it's not getting responses to any of its commands.Ultra-simple CFA-631 / CFA-633 / CFA-635 command-line communications example.
Crystalfontz America, Inc. http://www.crystalfontz.com
Usage:
./example-633 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/ttyUSB0" opened at "19200" baud.
Timed out waiting for a response.
Timed out waiting for a response.
Now, my natural first inclination is that the connection is bad or I've otherwise screwed up my wiring, but here's the *really* weird part:
Just on a lark, I tried "cat /dev/ttyUSB0" and pressed a button. Out popped an 8 byte sequence: 40 80 f8 71 40 80 9d d0, and it consistently produced similar sequences of bytes whenever I pressed a key. Next, I tried catting ttyUSB0 while the example program was running, and again, it was producing output. All this says to me that, yes, the LCD is sending response packets, but something in the software is failing to capture them.
My guess is that this might be some sort of version difference in how the serial interface works. Has anyone run into this or have a solution?
My setup:
Crystalfontz 633 HW 1.3 FW 1.5, connected using USB to serial converter on /dev/ttyUSB0
Ubuntu Intrepid Ibex (8.10), linux 2.6.27-11-generic
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