OSSC green led but nothing on the LCD display

[vgdiy]

Hey all, I got back a few 1.6 OSSC pcbs fabricated and assembled. I successfully programed them using a JTAG usb blaster using 0.77 jic file. When I turn it off and then on again, the LCD display backlight and the red led flashes on briefly, then the display and red led turn off and the green led turns on solid. Any idea where to start troubleshooting?

[Morpheus_79]

Did you see a test pattern, when you plug it to a screen or tv?

[vgdiy]

No test pattern on the screen.

[marqs]

It sounds like JTAG cnnection to FPGA works and you can write flash, but on power-up FPGA cannot load the firmware. Did you have “verify” enabled while programming .jic, and did it report success? If that went fine, I’d next check that MSEL pins are connected correctly.

[vgdiy]

the verify option was selected and the firmware reported success on completion. Ill take a look at the MSEL pins tomorrow.

[marqs]

Another thing to check is that FPGA properly gets 27MHz clock from the oscillator.

[vgdiy]

I just looked at pictures of my boards. the oscillator dot is not where the squared pin hole is. I have a feeling that is my problem. I will confirm tonight.

[vgdiy]

sorry for the delayed response, but fixing the oscillator fixed my problem.

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