Hey people,
I've made a PCB for a FV-1. Its running perfect when using the internal ROM (Jumper J3 shorted).
If I remove this jumper, T0 should be pulled to GND though the FV-1 should use the EPROM. But the FV-1 stops working which I can see on my bench power supply (power consumption drops from 120mA to about 80mA) and also my oscilloscope shows, that the oscillator stops working.
I tried using a higher capacitance on the crystal, but this made no difference... since the FV-1 is running great with the internal ROM, I really don't think that this is the culprit.
The jumper on J4 shorts pin 2 and 3 => EPROM gets supplied with 3.3V (verified with oscilloscope)
J5 is not used.
J6 is for selecting the program and is open, but it makes no difference if I put a jumper there or not.
Do you have any idea?!
The only thing I can think of is that the EPROM was not flashed correctly. I used this tutorial:
https://www.diystompboxes.com/smfforum/index.php?topic=121408.msg1156740#msg1156740And the Serial Monitor of the Arduino software says, that all bytes have been written successful.
Maybe I should try another EPROM Programmer? Any ideas what to use?
Thanks,
Chris
