Looking for fat Agnus, 8372A preferable... I have an 8375 that is the -18 VBB version, which won't work with 1MB chip in A500 Rev5, and I have an 8370 PAL Agnus already.
Hmm...don't know what You want to do with them,
just want to point out - chips You mentioned have different pinout, so it's impossible to use them on same board without adapter..
I thought any of those would run in an A500 and the only pinout difference was 8372AB (for the A3000)?
Ah, I checked - you are right of course. So I guess some models of 8375 are not compatible? I have an 8375 in there now that will not get past the second gray screen. Maybe that is the whole problem...
Nope!
You can use 8375 Agnus in A500 (not Plus),
However You need a special adapter (Megachip)
8370 will not fit, because You will get problems with refreshing due different RAM chip (rev 3 & 5 have 16 chips)
I currently have a rev5 board, and an 8370 works fine in it. I also have an 8375 that does not, but I need to check the version as I may have one with a different pinout.
It turns out that the 8375 318069-19 "VBB" seems to work just fine in my Rev5 A500. Crazy, eh? The list I found says this is the A3000 variant, when it clearly is not, and no adapter.
The ultimate problem turned out to be some traces I broke replacing all the RAM (what a pain, socketed 16 chips). It seems to run fine now...
Upon further work on this machine, it's still not right.
I have modified the board to allow 1MB chip RAM, but it would not work with the 318069-19 "VBB" Agnus. Green screen. However, it still works fine set up only as 512k chip RAM with no problem. I guess it is not pin compatible with the 8327A?
As you live in the States, I gather the Rev 5 board is NTSC, the following numbers are probably what you are after
( If you are not sure if it is NTSC or PAL, have a look at the Crystal (oscillator) near the Agnus, values 28.6363 = NTSC, 28.37516 = PAL)
(If you are not sure what the crystal is, google is your friend)
I have a 318069-02 in an NTSC A2000 MB.
Unfortunately I am still using it ATM, but I am thinking of converting this board to PAL and installing a megachip
If it becomes available and you are still looking will send you a PM
cheers,
Dan
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