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Apple II plus issue

I have finally gotten the chance to sit down and start to go over the Applesoft ROMS.

So far all the bytes that I have compared match. I still have a long way to go though.
The disassembly that the Apple 2 gives is different than the assembly listing though. Is that something to worry about even though the bytes match?
 
As long as the bytes match, the ROM's should be ok. The disassembly your comparing to could be for a different assembler. Are your Applesoft ROM's the correct part#'s ?
341-0011 for D0
341-0012 for D8
341-0013 for E0
341-0014 for E8
341-0015 for F0
 
I just checked the part numbers, and they all match. They did have -00 at the end, do that matter?

I want to point out an interesting thing I noticed while I was working on the Apple yesterday. While I was hitting the return key and reset to try to get into the monitor with the prompt at the bottom of the screen, question marks started appearing like they were being typed one after the other after one reset I did. Earlier I was experimenting with starting execution of Applesoft by issuing the ****G command in the monitor (where **** were the base addresses of the ROMS). I forget which ROM address I did that with (I think it was E0 or E8), but it also had the same results (question marks appearing) as the one reset cycle I encountered. I don't know if this is significant, but I thought I would point it out.
 
I just checked the part numbers, and they all match. They did have -00 at the end, do that matter?

I want to point out an interesting thing I noticed while I was working on the Apple yesterday. While I was hitting the return key and reset to try to get into the monitor with the prompt at the bottom of the screen, question marks started appearing like they were being typed one after the other after one reset I did. Earlier I was experimenting with starting execution of Applesoft by issuing the ****G command in the monitor (where **** were the base addresses of the ROMS). I forget which ROM address I did that with (I think it was E0 or E8), but it also had the same results (question marks appearing) as the one reset cycle I encountered. I don't know if this is significant, but I thought I would point it out.

The random keystrokes and also the early problems (beeping) you describe sounds like a flakey keyboard strobe signal or strobe reset.
Check pin 9 of the 74LS74 at B10 (from memory) it should only go high when a key has been pressed and will be reset the after the processor reads the keystroke. There are two 74LS257 at B6 and B7 they multiplex the RAM data inputs and the keyboard output, a bad socket contact on one of those can also cause all the symptoms you have. The keyboard multiplex select line and also the keyboard strobe clear are driven from the 74LS138 at F13, this is also a candidate for being to blame. Other chips that may be a problem but are less likely to be the cause are a 74LS02 at A12 and a 74LS04 at C11. Due to the intermittent nature of the fault it is unlikely that the chips are dead, I would look for tarnished legs on the IC's or possibly a faulty socket. If the chip legs are tarnished you can either replace the chips or very lightly sand the flat inner and outer edges of the legs with 400 grit sandpaper. If you are careful anything above 150 grit should work ok though.
 
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