[vcf-midatlantic] Bunch of Apple II clones for repair

[Neil Cherry]

On 1/2/24 19:12, Ricardo 8-Bit Desk via vcf-midatlantic wrote:

Ricardo, not sure of your background, mine is in software and hardware so
it come a bit more 'natural' to me. It's not natural until one learns
the details. Good news is that if you ask folks can help.

> I have no idea what state the computers are. I know for sure they need a good test on their power supply to start with.

NJ, definitely NJ (yes, bad joke).

> My knowledge of Apple II is very limited (more of a Commodore person) but I could NOT resist those last time I was in Brazil.
> 
> I will try to be there around 9-ish on Saturday.

I won't be there until Sunday, sorry.

> See you all there!

Suggestions (some folks may correct them or have much better ideas):

Check your power first, always. Then a quick check of the CPU clock and see
if the address are changing (both with an oscilloscope).

Tied the data buss to $EA (NOP) should step you through each address though
it will start at $EAEA (I think). I think you use a few resistors on the data
buss to pull the bits to 1 (1110 1010 - D7 - D0). At the ROM socket would
probably work okay. Might need to pull the RAM to check this.

Others will be able to help further at the workshop (and may have diag ROMS
to help).

Any Apple II, II+, or clone schematic will probably work okay for figuring
things out but a bit of guess work will be needed. A quick search of the net
should help. The operation of the Apple II will be very similar.

Weird, writing this down is making me think of how to debug my 68HC11 dev
board. :-)

-- 
Linux Home Automation         Neil Cherry       kd2zrq at linuxha.com
http://www.linuxha.com/                         Main site
http://linuxha.blogspot.com/                    My HA Blog
Author of:    	Linux Smart Homes For Dummies   KD2ZRQ