Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

TEXT LCD On DE1 Kit

I am trying once again to Add a text LCD to the Terasic DE1 kit like you see on DE2 kit and getting nowhere with it, Has anyone sucessfully done this?? I assumed I butchered the soldering on the first one and got a new one, still no response. The +5v power pin actually reads somewhere abotu 3.6 when I probe it, I wonder if thats the problem, tried every boot up combo there is to send to this, even signle stepped each bit of info sent and probed the pins.

Any Clues or advice, should I post the actual code or waveform file??

It's good to be evil.

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    17 years ago

    In DE2 the LCD is operated with 4.3V, a compromise to interface FPGA with LVCMOS IO standard. The module would operate with 3.3V also, but require a negative VCONT then and also have slower timing. When you watch 3.6 V supply voltage only, the circuit apparently is different from DE2, may it have other errors, too?

    To test the interface, you could attach a sources & probes instance and set the lines manually, you could also issue commands to LCD controller without recompiling the code.

    To check the control timing, I would like to see the waveform of a single command cycle from Quartus simulator or SignalTap. It should be clear also, if a necessary delay for the initial commands is achieved.