Hi where could I find all C64/ C-128 MOS chip pin info mainly I need to know
with each chip where Ground pin is?

I have the Howard Sams C64 repair manual it mentions a lot of the chips but no
DATA on the pins.

I looked n the C64 Programmers Reference manual but not much there.

I saw a utube video of a guy using a Multi-Meter set on OHM's but the highest
reading,
he mentioned finding the GND pin, then reading each pin should read very high. 
His findings revealed any low resistance
reading might indicate possible internal malfunctions, shorts etc (inside the
chip).  He was testing a PLA chip this way, then
inserted it into the chip socket, turned the power on, getting anything from
garbage screens, no startup message, no READY prompt
Blank or black screen (is what mine is doing)
etc.  He read a good PLA with high resistance readings and that PLA worked
okay.

Oh I forgot to mention in the PLA and maybe VIDEO test do the following:
Remove both CIA chips, and SID chip, then see what the startup does.

Will the C64 still startup without the PLA chip installed, I need to test the
VIC to maybe see if its bad, my Howard Sam's repair
manual mentions the VIC could cause a black blank screen?

The power source Im using is a known good unit so it must be a bad chip.

BTW my breadbin is a 1983 model
I have desoldered
2- CIA chips
1- PLA chip
SID has a socket

Once IF I can find the problem I will solder in chip sockets.

My Howard Sams manual says you can use toothpicks to temporarily test each chip
in its circuit without having to
solder anything, has anybody ever tried that?

BTW I found a cheaper Thermal Hot Air Desoldering unit on Ebay cheaper than the
Hakko (I may be spelling it wrong)
there are cheaper units like Hako but I could not find one.  The Hako was going
from $100 up to $700 .
My unit just has a fan that blows hot air but its still awesome.
I discovered this by watching utube videos on desoldering.

Anyway little off topic but if some dont know of this I thought I would mention
the Hako and Hot air devices only used for
electronics only.  My Thermal unit will even do heat shrink and some plastic
welding.

Utube is my buddy now. :)

Terry Raymond

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