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LCD CFA635 comes on, but host doesn't...


New member

I have a CFA635-TFE-KS LCD with the optional SCAB, an ATX power supply, and a MSP430 microcontroller as host.

The problem that I have is that when I turn on the ATX power switch on the LCD turns on but the host (MSP430 microcontroller) looks off, and is not sending anything to the LCD. Also I can not hear the ATX fan working. (The LCD keys do not turn on the host either)

The LCD communicates with the host using a RS232 cable. if I unplug the RS232 from the host, the LCD turns on, the host turns on, and I can hear the ATX fan working. After this I plug the RS232 cable and the LCD is displaying what the host is sending.

Any ideas why I'm having this problem? I do not need to turn on the host with the LCD keys, I just want everything start working when I set the ATX switch to power on.

I used command 28 with data \000, and then command 4, I do not know if these gives you any clues.

Thanks for your help!
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CF Tech

If you do a command 28 \000 followed by a command 4 then all the ATX functions of the firmware will be disabled.

If the LCD is on and your microcontroller is not, the SCAB is probably powering the LCD from Vsb, through JP8.

To disable the ATX functionality you will want to make sure that JP8 on the SCAB is closed and JP9 is open, then power the SCAB + CFA-635 through the floppy power connector on the SCAB.
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CF Tech

You have to open or close the jumpers with a soldering iron (sorry).

The explanation is on the SCAB manual on page 10.