I recently attended a VCFeast swap meet - it was fantastic being able to attend an in-person event! In any case, there I bought an apple ][ plus computer with no cards & 2 drives.
I ordered some parts, a keyboard encoder, a disk controller card, etc. I am so excited to get this running. I have a problem, however - the machine does not boot (yet)
could someone maybe get me going on the right track to solve this. Right now, I` get a screen full of characters in the following pattern:
??@@??@@??@@??@@??@@??@@
??@@??@@??@@??@@??@@??@@
etc
I have tried re-seating the ram chips in row D, and I have transposed the DIPs positioning.
I have reseated the ROMs
I moved a known working 6502 processor and switched out the proc on the board
none of these things have as of yet yielded any result.
I don't have an oscilloscope (yet) so I cannot really test the individual cpu lines.
Can someone please point me in the right direction?
When this computer was new, I was also new, and now we are both old. It's sort of one of those kind of situations (nostalgia). I never owned an Apple II, I was a c64 kid in the 80s and then Mac and Amiga in the 90s. I am quite excited to join the Apple II contingent, if possible.
Thanks,
Ron
I ordered some parts, a keyboard encoder, a disk controller card, etc. I am so excited to get this running. I have a problem, however - the machine does not boot (yet)
could someone maybe get me going on the right track to solve this. Right now, I` get a screen full of characters in the following pattern:
??@@??@@??@@??@@??@@??@@
??@@??@@??@@??@@??@@??@@
etc
I have tried re-seating the ram chips in row D, and I have transposed the DIPs positioning.
I have reseated the ROMs
I moved a known working 6502 processor and switched out the proc on the board
none of these things have as of yet yielded any result.
I don't have an oscilloscope (yet) so I cannot really test the individual cpu lines.
Can someone please point me in the right direction?
When this computer was new, I was also new, and now we are both old. It's sort of one of those kind of situations (nostalgia). I never owned an Apple II, I was a c64 kid in the 80s and then Mac and Amiga in the 90s. I am quite excited to join the Apple II contingent, if possible.
Thanks,
Ron