633 display/keypad freezing


New member
I have successfully integrated the 633 with my DSP hardware. Generally, the unit seems to be working well. However, occasionally, the display freezes and there is no apparent response to key presses.

I have not looked into this in detail yet, so cannot say for sure whether it's the 633 or my DSP. However, the DSP continues to run normally otherwise. Currently, the only means of recovery seems to be to switch off ond on again.

If anyone knows of an issue that might be cause this, and a way around it (like using the watchdog), it might save me some time.

Thanks in advance.
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CF Tech

Either you would have to send the display back to have an updated firmware loaded, or use the work-around:

It may be possible to send a reboot command (or several, until one is acknowledged) after the flash write, the reboot will restore the firmware to a stable state.


New member
Thanks for your prompt reply. I can confirm that I have H/W v1.3 and F/W v1.5, which is the version that DiamondWare were reporting the problem with.

I would prefer not to have to reboot the 633, as there would be some evidence of the 'glitch' on the display. If the problem has been fixed in a later release of the firmware, that seems the best way to go.

I need to deliver my design in the next few days and would like to test it with your new firmware before I do. To speed things up, is it possible for you to arrange an exchange rather than me returning the unit for upgrade?

USB LCD Displays - Graphic and Character LCDs with a Keypad