Power on


New member

I have a CFA-635 and have it working beatifully with FreeBSD, LCDproc etc.

I have also reprogrammed the startup message to say 'starting up'.

My question is that the LCD doesn't appear to power on (light up) until the USB port is scanned and identified by FreeBSD. Clearly power exists before that time, as the back LEDs are on dimly, but the unit otherwise looks like it is off.

Is there a command I can send to the unit to tell it to 'be on' from power on, rather than from USB initialization?

That would really help in a project.

Thank you :)
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CF Tech

USB is a power managed bus. We are not allowed to draw significant power until the OS enumerates the bus and enables us.

There are ways around it. If you DO NOT have a SCAB You can use a WRPWRY24:

If you DO HAVE a SCAB, you can connect power to the SCAB through the "floppy power" connector.

In either case, you will need to open JP2 on the module, so the USB cannot be "back powered" by the module. If you are using the SCAB, you will need to close JP8 on the SCAB.
USB LCD Displays - Graphic and Character LCDs with a Keypad