AMMRAM v1 - 1MB+ A500 chip upgrade

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Zetr0

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Hello there my fellow AmiBayers

I have a question for the masses -

Currently I have my VXL*030 in my A500+ (thanks Jimmers)

Now as we know the A500+ has 1MB of ram as standard and I blelieve that the slot is passive and hence would take another 1MB of ram without needing extra address lines like the A500 does.

So, what the question I hear you tapping - well

Let me introduce the AMRAM v1

(note that this is in a dual card configuration)
P1010643.jpg


Features
  • 1 MB RAM - gives 1.5 MB total
  • eight 256k×4 DIPs soldered onto the board
  • connects to the trapdoor slot
  • an adapter board connects to the Gary socket
  • expandable with a standard 512 kB trapdoor slot RAM expansion (not exceeding 9 cm in length) for 2 MB total
  • disable switch
  • requires Kickstart 1.3

So Heres the Question

As a single card (with 1MB) would this function in an A500+ without the need for the Gary Adapter ?

P1010645.jpg


Any ideas welcome,

heres another pic =D

P1010642.jpg
 
Nope, I don't think it would. The memory appears in a different location, so i doubt that it would work without the gary clip.

The 500+ expects a 512kb or 1MB chip RAM expansion in there, and I assume has the address lines to support this. I can't remember the address, but I believe that's in the first 2MB of the 68000 space.

The 500 expects 512kb of slow mem, no more, and that's why the gary clip is needed... Slow mem is at c00000, and there's a hole of 1.5MB in the space so I guess the clip is needed because the address lines are missing from the expansion slot?

For a definitive answer, check the expansion pins or see if someone's already tried it :D
 
It could be possible to modify this very easily, unfortunately I don't have proper schematics here.

(it is naturally possible to modify it, but is it worth your while is another question)
 
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