Closed Megachip for A500, A2000, and CDTV (rj1307 project, Poland)

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Would be interested in one piece without Agnus, if any are still available?
Hello,
Yes, still available, need to solder them up, though
Will build & test them and then come back to You with payment details
regards,

Viktor
 
Just a small update:
Started to delivery second batch
1×Megachip was sent to Jim_Oregon (tracking info in PM)

@hlide
Was it just a question or You wanted to declare interest?

Sorry, that was just a question I could answer myself.
 
Parcels for BigSupes and SukkoPera was sent
tracking info will be available in PM

added user britlord to gueue


- - - - Update - - - -
payment details sent to viserys23 & optiguy
 
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I think he's building them one at a time and will let you know when it is your turn.
 
Payment received from users optiguy & demolition
dear britlord , please be patient, have added You to queue two days ago, there are some members for You (You can see all info in first post)
will send You payment info once Your device is ready built and tested (i have NO pick'n'place machine, all boards are soldered by hand if my free time, Sorry i cant do it faster with same quality )
 
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Payment received from users optiguy & demolition
dear britlord , please be patient, have added You to queue two days ago, there are some members for You (You can see all info in first post)
will send You payment info once Your device is ready built and tested (i have NO pick'n'place machine, all boards are soldered by hand if my free time, Sorry i cant do it faster with same quality )

OK No Problem (I did think that you was busy)...
 
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Great news, will let you know when it arrives

Sent from my SM-G930P using Tapatalk
 
..Do you have installation instructions available based on board revision number? Basically what do I do with the single wire that is included. I know it should run from the megachip to the motherboard but where on the motherboard?
Hi,
Glad to hear Your parcel arrived. Instructions are as follows:
1. Desolder old PLCC Agnus socket
2. Solder in a new one that was delivered with adapter
3. Insert new adapter (be careful and watch the correct position of Pin1
4. Connect A20 wire to A20 signal on the motherboard (grab a multimeter and find the nearest point to the Megachip)
5. Install new Agnus and run systest (scan memory)

Enjoy 2MB ChipRAM
Hi, what power output should I be looking for with the multimeter?

Sent from my SM-G950F using Tapatalk
 
A20 can be found on Gary (U5) pin 36 or the CPU (U1) pin 48 so you could choose to connect the wire against one of these two pins. It is also connected to one of the pads in JP5 on A500 Rev 6 boards, but this is where the multimeter comes in handy as you can use the continuity test to verify against the known point on U1 which is A20 on all revisions.

This is the schematic of A500 rev 6 and you can search for A20 to find the locations:
https://www.amigawiki.org/dnl/schematics/A500_R6.pdf
 
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