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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Prot88 on June 23, 2012, 08:19:14 AM

Title: A1000 - How to reduce available memory ?
Post by: Prot88 on June 23, 2012, 08:19:14 AM

Hi

I have troubles with a Amiga 1000 Golem ram expansion.

Each time I reach 800 Kb of 2 Mb available I have a guru.
I tried to change memory chips but no change.

So, I need to tell my workbench 1.3 not to use bad memory.

I have tried with nofastmem + addmem (start memory) (end memory) but it doesn't work (memory already mounted).

I tried to disable memory with the switch and addmem : no ram expansion found.

Another idea ?

Title: Re: A1000 - How to reduce available memory ?
Post by: Zac67 on June 23, 2012, 09:42:19 AM

Run a RAM tester - sometimes there are bad contacts/sockets that make memory fail.

Title: Re: A1000 - How to reduce available memory ?
Post by: Megamig on June 23, 2012, 01:30:19 PM

Quote from: Prot88;697638

Hi
 
I have troubles with a Amiga 1000 Golem ram expansion.
 
Each time I reach 800 Kb of 2 Mb available I have a guru.
I tried to change memory chips but no change.
 
So, I need to tell my workbench 1.3 not to use bad memory.
 
I have tried with nofastmem + addmem (start memory) (end memory) but it doesn't work (memory already mounted).
 
I tried to disable memory with the switch and addmem : no ram expansion found.
 
Another idea ?

Solution: Slice the Amiga in half *jokes* :crazy:

Title: Re: A1000 - How to reduce available memory ?
Post by: mechy on June 23, 2012, 07:17:29 PM

Quote from: Prot88;697638

Hi

I have troubles with a Amiga 1000 Golem ram expansion.

Each time I reach 800 Kb of 2 Mb available I have a guru.
I tried to change memory chips but no change.

So, I need to tell my workbench 1.3 not to use bad memory.

I have tried with nofastmem + addmem (start memory) (end memory) but it doesn't work (memory already mounted).

I tried to disable memory with the switch and addmem : no ram expansion found.

Another idea ?

Have you tried this ram expansion on another machine and if so did it work correctly? its likely if its seeing only some ram the way you describe you may never see reliable operation on any amiga. If the ram was not bad then its something in the golem (pal? gals? etc?). i wonder if this is a case of the A1000 bad grounding on some revisions? have you considered running the ground wires to see if it helps?

mech

Title: Re: A1000 - How to reduce available memory ?
Post by: kamelito on June 23, 2012, 10:19:11 PM

Quote from: Prot88;697638

Hi

I have troubles with a Amiga 1000 Golem ram expansion.

Each time I reach 800 Kb of 2 Mb available I have a guru.
I tried to change memory chips but no change.

So, I need to tell my workbench 1.3 not to use bad memory.

I have tried with nofastmem + addmem (start memory) (end memory) but it doesn't work (memory already mounted).

I tried to disable memory with the switch and addmem : no ram expansion found.

Another idea ?

 You can do an AllocAbs() early on, I remember the opposite a hack to addmem() an A1000 with a Phoenix board, you had to inserted the hex values of the addmem to the Kickstart WOM, this was placed in the kickstart hand picture, so it was a bit corrupted but worked great. It's probably available somewhere in the net, maybe even Aminet :) Kamel

Title: Re: A1000 - How to reduce available memory ?
Post by: Terse on June 23, 2012, 10:26:25 PM

Quote from: Prot88;697638

Hi

I have troubles with a Amiga 1000 Golem ram expansion.

Each time I reach 800 Kb of 2 Mb available I have a guru.
I tried to change memory chips but no change.

So, I need to tell my workbench 1.3 not to use bad memory.

I have tried with nofastmem + addmem (start memory) (end memory) but it doesn't work (memory already mounted).

I tried to disable memory with the switch and addmem : no ram expansion found.

Another idea ?

A utility called memeat, available on aminet can cordon off blocks of RAM, but I do not believe you can specify an address range.

I'm not sure if any addmem command can specify a bank of RAM on an expansion board to be allocated.  

I do agree with the posters above that grounding issues in the A1000 are about as likely as a bad RAM chip (maybe 50/50 chance.) Are you sure it's the RAM board?   Have you been able to try other expansions on this 1000, or this 1000 using other expansions?

Title: Re: A1000 - How to reduce available memory ?
Post by: Prot88 on July 01, 2012, 09:31:54 PM

I have grounded all my expansion devices. I will try memeat.

Before that, I must solve a Hard drive issue (see http://www.amiga.org/forums/showthread.php?t=62029) I have unplugged the memory expansion to be sure it is not the problem.

If I succed format the drive I will plug the memory.

Thanks !

Title: Re: A1000 - How to reduce available memory ?
Post by: shaf on July 01, 2012, 10:28:41 PM

Did you also do the Daughterboard Ground Mod?

Title: Re: A1000 - How to reduce available memory ?
Post by: danbeaver on July 02, 2012, 01:33:27 AM

If you've replace the questionable memory chips with working chips. , it is not the memory but either the memory controller or damaged address lines. I would have someone (or do it yourself) check the continuity of the address lines. And as stated try the device on another system. It might be repairable or replaceable. Also make sure you connections are cleaned of oxidation.

Title: Re: A1000 - How to reduce available memory ?
Post by: Ratte on July 02, 2012, 03:30:11 PM

Boot your A1000 with TwinKick (Aminet).
During (os1.3) resets you are able to disable all expansions (ext. diskdrives, hdds, memory) by holding both mousebuttons.
You will see a short colorflash for the "gaming-mode".
With the next reset all expansions are available again.
(Or you can jump directly to os3.1 )

Disabling fastmem with nofastmem + addmem will crash the system with a corrupted memlist.

Disabling memory with TwinKick + addmem is possible.