Can anyone identify this RAM expansion board??

[fc.studio]

Originally Posted by PowerPie5000

This is a 2mb expansion for a standard A500 with a Gary adapter! It's not very common or easy to find.... there are plenty of 512k expansions but i want more ram than the standard 1mb

I had the RA5-2MB board, then I sold it last year as partial working since a friend of mine was amused on repairing the broken pins. Unfortunately I had anymore a standard A500 to test it but on an A500+ it worked as a +512kb.
However I'm enough sure that on my previous standard A500 with 1.3 ROM Kickstart and some ECS chips this board gave me +1,8 MB Fast (Slow) RAM and not 2 MB. On removing an horizontal (or vertical?) serie of RAM chip I got +1,5MB RAM. I had it for free many many years ago but unfortunately it came without instructions and perhaps not fully working.
I never got the 1 MB CHIP RAM from my A500 although I had the proper Gary and I tried any wire/jumper combination.

[PowerPie5000]

Ok everything is sorted now! Spent a while today scrubbing the corroded part of the board.... and to my surprise under all the crispy green crap there were intact copper traces (i gently scrubbed the corroded traces with soft wire wool to reveal fresh intact copper underneath all the crap ). I also got rid of the leaky battery (who needs a clock anyway when gaming )

I also sorted out the blob of solder on one of pins/legs on the Gary adapter... it now sits firmly in place

I cleaned up the A590 that i bought for £14.99 and attached it to my other A500 and also popped in the cleaned up 2mb expansion board and Gary adapter. I was going to use it all on my ancient A500 with red power led but it did not detect all the memory... so i let that one have the GVP HD8+

And this one is using the A590 and ram expansion (4.5mb total ram). This is my favourite A500 and is in truly excellent condition with absolutely no yellowing! I wonder how much this setup is worth?

[alexh]

Not very much I imagine.

Less than an A1200.

[PowerPie5000]

Originally Posted by alexh

Not very much I imagine.

Less than an A1200.

Oh well it doesn't matter anyway as i am keeping it! All the other A500's i see being sold on ebay are really showing their age and never look too good

I also have 2 x A1200's (always keep a spare )

Oh by the way, thanks for offering to repair the board seems it really was not as bad as i thought!

[fc.studio]

Does it add 1.8 or 2 MB RAM?

[PowerPie5000]

Originally Posted by fc.studio

Does it add 1.8 or 2 MB RAM?

It adds 2mb ram with with my rev 5 A500. My older A500 with a rev 3 motherboard could not detect or initialize all the ram... Not exactly sure why

[fc.studio]

Originally Posted by PowerPie5000

It adds 2mb ram with with my rev 5 A500. My older A500 with a rev 3 motherboard could not detect or initialize all the ram... Not exactly sure why

I'm curious, so I try to ask you more:

To be sure: did you check the total RAM size using SYSInfo (or AIBB) tool and disabling your hard drive with extra RAM installed?

...and more: did you try to have 1 MB CHIP memory on your A500 using this RAM expansion?

...finally: I would like to know if this board works on the A500+ coming with 1 MB CHIP RAM and ROM 2.0. Could you have the opportunity to test it on this upgraded Amiga 500 model?

[PowerPie5000]

Originally Posted by fc.studio

To be sure: did you check the total RAM size using SYSInfo (or AIBB) tool and disabling your hard drive with extra RAM installed?

I checked the total using a Microbotics utility disk (came with one of my A1200 boards but the disk runs on any amiga). It showed up as a total of "4,718,592" bytes - this includes the ram on the A590. Without the A590 it shows as "2,621,440" bytes. (2mb ram board + 512k chip)

Originally Posted by fc.studio

...and more: did you try to have 1 MB CHIP memory on your A500 using this RAM expansion?

I have not tried the 1mb chip ram configuration using this expansion... will i need to change jumpers on the motherboard or change the Agnus chip? The utility i have does not go into detail

Originally Posted by fc.studio

...finally: I would like to know if this board works on the A500+ coming with 1 MB CHIP RAM and ROM 2.0. Could you have the opportunity to test it on this upgraded Amiga 500 model?

I'm afraid i don't have an A500+ so i cannot test this board with one!

I am not 100% sure how my ram is configured... but i am guessing it is 512k chip with 4mb fast/slow in total

[Skylight]

Better check with SysInfo what kind of memory and how much ur A500 got.
http://aminet.net/util/moni/SysInfo.lha

2MB Slow-RAM is not possible.
Maximum is 1.8MB in the reserved area from $C00000-$DFEFFF.
Since the chipset registers will start at $DFF000.

And real Fast-RAM ($200000-$9FFFFF) needs a connection to the CPU socket.


Ciao, Rick ...


EDIT: Trapdoor expansions can use only the address range from $C00000-$DBFFFF (less than 1.8MB) with an Gary adapter but without CPU adapter.
Since there is the real time clock from $DC0000-$DCFFFF.
But they can increase the Chip-RAM ($000000-$1FFFFF) too.
So better check ur RAM and the addresses. SysInfo will tell u.

[PowerPie5000]

Originally Posted by Skylight

Better check with SysInfo what kind of memory and how much ur A500 got.
http://aminet.net/util/moni/SysInfo.lha

2MB Slow-RAM is not possible.
Maximum is 1.8MB in the reserved area from $C00000-$DFEFFF.
Since the chipset registers will start at $DFF000.

And real Fast-RAM ($200000-$9FFFFF) needs a connection to the CPU socket.


Ciao, Rick ...


EDIT: Trapdoor expansions can use only the address range from $C00000-$DBFFFF (less than 1.8MB) with an Gary adapter but without CPU adapter.
Since there is the real time clock from $DC0000-$DCFFFF.
But they can increase the Chip-RAM ($000000-$1FFFFF) too.
So better check ur RAM and the addresses. SysInfo will tell u.

So does that mean the utility i am using is detecting the memory although a bit of it may not be usable? It detects the full amount installed but does not tell me how much of that is available or usable.... so for the ram board with the Gary adapter it will tell me on screen there is 2mb although only 1.8mb can be used?? This is confusing

Basically the Microbotics util will tell me whats installed in total but does not tell me how much can actually be used! Also what are the requirements for running Sysinfo? My A500 uses KS 1.3 and WB 1.3, cheers

[Skylight]

SysInfo will work on any A500.
It was my favorite tool to check my AMIGA's and is part of my maintenance boot disk.


Ciao, Rick ...

[orange]

I bought such card (actually the same as in alexh photos) from amibay few months ago. it had some acid damage and battery was missing. but it worked, passed all RAM test.
they seem robust, so I believe yours will work too.

didn't test the clock, though, for obvious reasons.

edit: missed the second page, oh well...

[PowerPie5000]

Originally Posted by Skylight

SysInfo will work on any A500.
It was my favorite tool to check my AMIGA's and is part of my maintenance boot disk.


Ciao, Rick ...

Only one problem... i have not yet got myself a CF kit for my A1200 so i cannot transfer the sysinfo from my PC to the Amiga I do not have a null modem cable either and i know i cannot create an Amiga disk on a PC without a catweasel

All my Amiga's are really only ever used for the hundreds of games i have on disk.... nothing else really so i have not bothered getting CF cards or WHDload etc... but i will do eventually

[Skylight]

"SysInfo" created by Nic Wilson was spread on different PD series too.
Especially Fish disks.
http://www.amiga-stuff.com/pd/fish.html

So maybe u can get a PD disk with SysInfo.

The last version was 3.24.
(And it will only tell u about 1.5MB Slow-RAM since counting in 512k steps above 1MB, but the addresses r right.)

SysInfo looks like this:

[Skylight]

Originally Posted by PowerPie5000

Only one problem... i have not yet got myself a CF kit for my A1200 so i cannot transfer the sysinfo from my PC to the Amiga I do not have a null modem cable either and i know i cannot create an Amiga disk on a PC without a catweasel

But ur A1200 can read PC DD disks with FAT12 if u got PC0 mounted .. and if u got only HD disks then cover the HD hole.


Ciao, Rick ...

[prowler]

Originally Posted by Skylight

"SysInfo" created by Nic Wilson was spread on different PD series too.
Especially Fish disks.
http://www.amiga-stuff.com/pd/fish.html

So maybe u can get a PD disk with SysInfo.

The last version was 3.24.
(And it will only tell u about 1.5MB Slow-RAM since counting in 512k steps above 1MB, but the addresses r right.)

http://www.config.freeuk.com/amiga/progs/sysinfo324.lha

[PowerPie5000]

Originally Posted by Skylight

"SysInfo" created by Nic Wilson was spread on different PD series too.
Especially Fish disks.
http://www.amiga-stuff.com/pd/fish.html

So maybe u can get a PD disk with SysInfo.

The last version was 3.24.
(And it will only tell u about 1.5MB Slow-RAM since counting in 512k steps above 1MB, but the addresses r right.)

SysInfo looks like this:

I probably have a disk with this on somewhere as it seems very familiar! Time to hunt through hundreds of disks

[PowerPie5000]

Originally Posted by Skylight

But ur A1200 can read PC DD disks with FAT12 if u got PC0 mounted .. and if u got only HD disks then cover the HD hole.


Ciao, Rick ...

I learn something new everyday! thanks

[prowler]

Originally Posted by PowerPie5000

I probably have a disk with this on somewhere as it seems very familiar! Time to hunt through hundreds of disks

Originally Posted by prowler

http://www.config.freeuk.com/amiga/progs/sysinfo324.lha

Originally Posted by Skylight

But ur A1200 can read PC DD disks with FAT12 if u got PC0 mounted .. and if u got only HD disks then cover the HD hole.

[Skylight]

Originally Posted by prowler

http://www.config.freeuk.com/amiga/progs/sysinfo324.lha

Version 3.24 is available at AMINET too and the link was already in post #49 above.