635 serial version no response


New member

I have here a CFA635 TMF KS.

It worked last time it was used some months ago, on a PC that no longer exists. Now, when I apply power, I get a good boot screen and backlight, but it doesn't respond to serial commands using the 635 wintest program. I'm using a USB to serial converter that identifies to windows as "Prolific USB-to-Serial Comm Port (COM6)". I've tried selecting different baud rates and issuing various commands, but it just sits there timing out on the version query commands the program uses to detect a display. There is also no report of key events.

This seems like a pretty fundamental comms problem; are there any known issues with USB to serial converters, or anything else I could try?


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CF Support2

I connected up a CFA635 KS (full swing RS-232 with daughter board) to a Prolific USB-to- Serial adapter to verify. I was able to communicate to the module without any issues with both our current shipping firmware, and the previous version. I did not adjust the COM port to any particular speed or setting - it comes up at 19200-8-N-1. The module will communicate via 635WinTest at 19200 or 115200. 115200 is the default for the module.

What cable are you using from the Prolific adapter to the module's daughter board? I'm am using our WR232Y08 - which is "straight through", no cross-over.

USB LCD Displays - Graphic and Character LCDs with a Keypad