Amiga 3000 zip ram problem

[Zac67]

I've found something intersting: I moved 1MB of chip ram to the fast ram DIP sockets and it works !

With or without moving the RAM size jumpers (J852/853)?

If DIP 256kx4 work and ZIP don't it's clearly a problem with the sockets.

[VingtTrois]

With or without moving the RAM size jumpers (J852/853)?

If DIP 256kx4 work and ZIP don't it's clearly a problem with the sockets.

Or a problem with one of each 1M (2 chips = 1MB) of ZIP chips!
Do you have a warranty for your ZIP Ram memory?

For the FPU, read this: http://www.amiga-hardware.com/downloads/a3000fpuupgrade.jpg
Check with SYSINFO or AIBB if your FPU is at 42MHz ?!?

[agr]

Yes, with moving J852 to the 256k4 position. This board (rev 9) does not have J853.
I tested the connections between DIP and ZIP sockets bank 0 and they seem ok.
I re-tried now to put the DIP chips and they aren't recognized anymore (they are still ok in the chip ram section).

[Zac67]

You should try testing the RAM by absolute address even if it's not added to the system pool, it should be there all the same.
I'm sure I had some tool for that but can't find it atm...

[VingtTrois]

@agr: or simply electrostatic discharge (ESD) have destroyed all these chips! :-(

[agr]

@VingtTrois I'm equiped with ESD condoms (antistatic wrist strap and desk mat).

I'm interested by the absolute memory testing solution, this is what the system may do to detect the ram chips...

[VingtTrois]

@VingtTrois I'm equiped with ESD condoms (antistatic wrist strap and desk mat).

I'm interested by the absolute memory testing solution, this is what the system may do to detect the ram chips...

I can test for you each chips (for free), on A3000/030@25MHz Rev9.3 + 2x OKTAGON 2008.

[agr]

@VingtTrois
This is very nice of you Thank you, but I just bought one of those Oktagon 2008 as you are using to test the chips. So if they work on the Oktagon, I will have 8Mb usable for sure. I guess this ram will be slower... but I just need a good working Amiga as a reference machine for my hobby development of AROS.

I still have to:
- replace the leaking battery
- install the network Xsurf card + AmiTCP or something

[SpeedGeek]

There is a clock speed jumper for Ramsey (J851) and a clock 90 jumper (J100) both need to be set for 16 or 25 Mhz. Most A3000's are 25 Mhz. But it's a good idea to check jumpers in any case. Your problem is most likely an open connection to any one of the ZIP chips. Could be a bent pin, poor solder joint or broken trace. If the OS can't find memory in the first bank it won't bother to check the others. It's worth the effort to fix the problem. ZorRam will only run at 2/3x speed of motherboard fast memory and supposedly only works with SuperBuster rev 11. As far as the 42 Mhz FPU mod, someone went to alot of trouble to do this. There's a simple cut and jumper mod on Aminet/hardware/hacks to run the FPU from the motherboard 50 Mhz oscillator. You won't see a big performance boost since the FPU is seldom used by the OS. Looks nice on Benchmark programs though.

[agr]

There is a clock speed jumper for Ramsey (J851) and a clock 90 jumper (J100) both need to be set for 16 or 25 Mhz.

All these jumpers are set to the 25MHz position, like on:
http://amiga.resource.cx/photos/photo2.pl?id=a3000&pg=7&res=hi&lang=en
same board, same chips config, same jumpers

Your problem is most likely an open connection to any one of the ZIP chips. Could be a bent pin, poor solder joint or broken trace.

I checked with a multi-meter, the DIP and ZIP sockets are connected on bank 0; seems ok to me and I just don't like to remove the motherboard completely...

It's worth the effort to fix the problem.

Yes, I'm trying to :hammer:

Can someone post a ShowConfig output of his A3000 with FastMEM on the motherboard ? Thanks

I'm trying with a little prog to write then read a value back from the FastMEM, according to this memory map: http://gega.homelinux.net/AmigaDevDocs/hard_d.html#d-2. I tried $0700 0000 without success :furious:

[spirantho]

Or you can use one of the memory testers on Aminet. There's a few of them, I've used one which was originally designed for A1000 expansions I think....

[Zac67]

RAM grows from $07FF FFFF downwards, so Bank 0 is 07C0 0000-07FF FFFF.

This was apparently done to get a contiguous chunk with accelerator RAM.
The RM is wrong as RAM starts at $0700 0000 for 16 MB, 64 MB were reserved for 'future' mainboard RAM.

[agr]

I tried also 07F0 0000 as I have now 1MB: no success.

I've found a diagnostic rom for Amiga Forever (I have a license): logica-dialoga-200.rom. This may test better my A3000; it looks fine in WinUAE. How can I load this ROM (512k file) into my A3000 ?

[SpeedGeek]

I checked with a multi-meter, the DIP and ZIP sockets are connected on bank 0; seems ok to me and I just don't like to remove the motherboard completely... Yes, I'm trying to
The 1 meg Zips use one more multiplexed address line (ADDR 9) than the 256K Dips use. But if your sure you have continuity from the Dip to Zip sockets on all pins then the open connection could be from Ramsey to the Dip sockets. Also, J852 is long way away from Ramsey so I would check for possible open connection there. One side has +5V, the other Ground and the center to Ramsey pin 12. A3000 Schematics can be downloaded from many websites. A good small program from Aminet is Checkmem. Use the "Force" option to check areas outside of the memory list and use with Cpu Nodatacache.
Can someone post a ShowConfig output of his A3000 with FastMEM on the motherboard ? Thanks
RAM: Node type $A, Attributes $505 (FAST), at $7000000-$7FFFFFF (16.0 meg)

[agr]

I bought an Oktagon 2008 on eBay, just for testing my zip ram chips and there is a problem at boot. The autoconfig screen shows this board 2092/8 as DEFECTIVE.

What do you think ?
a) my chips are defective
b) the Oktagon is defective

@VingtTrois I will have to send you my chips for testing. If you agree, please send me your address.

[zipper]

Take the chips away and look again.