Nexus SCSI card RAM problems

[skote]

So... Now the A1500 is up and running I want to put more RAM in the old girl. I have a Nexus SCSI card which has 4 RAM slots - 2 for 4MB and 2 for 2MB 30 pin SIMMS. I have a load of 30 pin SIMMs (1 MB and 4MB from a pair of 386s) that I have acquired and want to use them. When I slot them in the board in the right slots and use the jumper on the board to config the RAM, I get a red "Bad Card" screen until I take the RAM out. The only information I can find about this card online is on Amiga.Resource.cx and of course Amiga-Hardware. Neither of these are comprehensive though, nor do they include the manuals as .pdfs. Does anyone know anything about this card, what RAM (do I have the right voltage and speed for example?) it takes and how to configure it? I've got 7MB (1 MB Chip, 4 MB Fast on A2630 and 2 MB Fast in another Zorro slot) but taking it up to 9 MB in total would be nice for my impending OS 3.5 install......

[rkauer]

Originally Posted by skote

So... Now the A1500 is up and running I want to put more RAM in the old girl. I have a Nexus SCSI card which has 4 RAM slots - 2 for 4MB and 2 for 2MB 30 pin SIMMS. I have a load of 30 pin SIMMs (1 MB and 4MB from a pair of 386s) that I have acquired and want to use them. When I slot them in the board in the right slots and use the jumper on the board to config the RAM, I get a red "Bad Card" screen until I take the RAM out. The only information I can find about this card online is on Amiga.Resource.cx and of course Amiga-Hardware. Neither of these are comprehensive though, nor do they include the manuals as .pdfs. Does anyone know anything about this card, what RAM (do I have the right voltage and speed for example?) it takes and how to configure it? I've got 7MB (1 MB Chip, 4 MB Fast on A2630 and 2 MB Fast in another Zorro slot) but taking it up to 9 MB in total would be nice for my impending OS 3.5 install......

As I said before, more than 6Mb RAM in the Zorro auto-config space will make you very dismayed!

ZorroII interface is only 8Mb-wide. And you need some space for your cards to auto-config.

So... Only if (and only if...) you acquire an accelerator with its own RAM, you are limited to 6Mb Fast RAM(or even 7, no more than this). Nothing is impending you to have 2Mb of CHIP RAM, installing a CHIP RAM doubler).

[skote]

Indeed. I remember your advice very well.
I tried the SCSI card int he absence of any other Zorro card and it still said "bad", leading me to conclude I have either config'ed the card wrong, or the RAM is imcompatible (it might be bad but he guy who gave it me is trustworthy).

[rkauer]

Originally Posted by skote

Indeed. I remember your advice very well.
I tried the SCSI card int he absence of any other Zorro card and it still said "bad", leading me to conclude I have either config'ed the card wrong, or the RAM is imcompatible (it might be bad but he guy who gave it me is trustworthy).

Looking TBBoAH, I may nailed down your problem (quote):

Note: The Nexus could NOT handle all sorts of SIMM modules.
Following SIMM types (1Mx9) seem to work correctly:
HYM91000S Siemens
MC421000A9A/A9B NEC
MSC2312AYS9/AKS9 OKI
THM91000AS/AL Toshiba
Don't use SIMMs 1Mx8! These ones don't work properly.

[Zetr0]

look like it requires parity simms.... interesting...

amiga resource doesn't mention it... hmmm

[skote]

Yes, I looked in all the standard places and got no answers. I will have a look at what SIMMs I have when I get home. I suspect they are incompatible then, and finding "correct@ ones is going to be somewhat problematic. Thanks Rkauer.

[rkauer]

Originally Posted by skote

Yes, I looked in all the standard places and got no answers. I will have a look at what SIMMs I have when I get home. I suspect they are incompatible then, and finding "correct@ ones is going to be somewhat problematic. Thanks Rkauer.

You're welcome, m8.

[Zetr0]

@Skote

just to help you on your quest

(1 x 9 )* 4 (4MB total) 30 PIN SIMM Parity $3.99

4mb * 4 (16mb total) Parity 30pin simms $9.99

1mb * 100 (100mb total) Parity 30 Pin simms $69.99 (BECOME THE SIMM BARON!... it is your.... destiny.... )


anyway all of these will ship world wide for around $8 so just PM them and make sure.

hope it helps m8y.

[skote]

Nice one Zetro!
My mates already think I am mad for buying some Amiga kit. I had one over for beers the other night and was fiddling with the A1500. He said to me:

"WTF is that old piece of sh*t for?"

Before mocking my retro items. After a few more ribbings about:

"The only computer that will be left after a nuclear blast"

etc etc I handed him my 80's mingin' Powerplay stick (pink, yellow and lime green... mmmmmm ) and loaded Speedball 2 on the A1200. He didn;t speak for the next 40 minutes, apart from to say

"Get me another beer mate"

Perhaps he will be another Disciple to the Cause?

Thanks for the links. I wil have a look when I get home.

[fryguy]

damn.. i just bought 2 30pins 4mb simms for my Nexus card. Hope they work. If they do i will update with brand name etc.

[skote]

And because I hear Zetro likes hardware pr0n......

[Zetr0]

@skote

mmmmmm very nice

thank you very much indeed

[skote]

If I get hold of that RAM you showed me on eBay (thanks! ) I will photo them for you too... and installed in the board!

[Zetr0]

NIIIICEEEEE!!!!


see thats how one makes Zetr0 happy

[fryguy]

Mine also says defective when i put the two "new" 4mb simms in :/
I have an A4000 with the standard 030/25 board.

Can i only use 6mb on the card as i have other zorro boards in the system?
Or is it that my simms aren't compatible?

[rkauer]

Originally Posted by fryguy

Mine also says defective when i put the two "new" 4mb simms in :/
I have an A4000 with the standard 030/25 board.

Can i only use 6mb on the card as i have other zorro boards in the system?
Or is it that my simms aren't compatible?

Zorro-III don't have the 8Mb space limitation as Z-II have. It have a 32bit address space (~4Tb, theoretically) outside the 8Mb window!

The problem in this particular board is it requires SIMM with parity! Those SIMM with an even number of chips don't work at all.

[skote]

Right then.
Zetro kindly sent me some 30 pin SIMMs and I got cracking with them. They failed to let me boot or even go through the stratup sequence unless I closed the Memory Test jumper. I then got the machine to boot and ran a test, getting green lights on the test software with either SIMM installed, but reds with both, and consistently got a "word write at $ffff" error. Or something. Big Z unfortunatley didn't test the RAM before sending it my way (which was gratefully received in any case btw Zetro ) so I dunno if my card is b0rked or not.
Now for the HDD. The Nexus previously reported that the drive was 170MB and then it apparently mangled itself. It spins up fine and sounds OK, and seems to seek, but it does get rather hot to the touch (is this normal for older drives?). I used my Xetec FastTrak and managed to resurrect it. It bizarrely reported itself to me 1GB in size which confused me. I typed all the serial numbers into Google and the IBM website, but couldn't find any specs. I then found that it reported itself as a 0662 S12 to the Amiga and found this:

http://insight.actapricot.org/insigh...hard/i0662.htm
http://stason.org/TULARC/pc/hard-dri...CSI2-FAST.html

It is indeed a 1GB drive. So, I formatted and partitioned it but plugged into the Xetec controller KS didn't recognise it. I plugged it back into the Nexus controller and used that to make the partition FFS and BOOT, and then successfully installed WB 3.0 onto it.
I shut the whole thing down last night to commune with humans rather than retro kit and got a ZIP file of ClassicWB ready.

When I fired it up this morning I felt rather . AmigaDOS appeared and told me "Not a DOS disk in device DH0:". Hmm..... I used my Nexus utils again and the drive this time reported itself as 3.8GB, but made the software hang (yellow screen and then a Guru Meditation error). On the next boot, the drive then decided that ti was 170MB again and would not format. Erm........

So. I am going to try again, this time taking a cue from the websites above in an attempt to try to force the drive to accept some parameters.
Does anybody have any suggestions about this problem, or should I just send the drive for "recycling" and buy another one; or worse, do I have 2 knackered SCSI controllers? (The KS3.1 early boot screen reports them both working.....)

[skote]

So, either it is a weekend lull, or nobody is interested. .
Neither controller could see the HDD so I manually entered the parameters via my Xetec controller, partitioned and formatted it. It s now working and I have successfully put ClassicWB on it. However, I had to call it "DH0:" as the name or the ClassicWB instal failed. Is this an "assign" problem? Also, HDToolBox can't see it either. WTF?

The SIMMs on a Nexus must be installed in pairs starting with the slots nearest the gold edge connector. As the jumpers suggest the only options are 2, 4 or 8MB installed using two or four 1MBx8 SIMMs for 2 or 4MB, and two 4MBx8 SIMMs for 8MB. Since you have 6MB already installed you can only add 2MB using two 1MBx8 SIMMS.
My Nexus card stopped working I think because the EPROM has lost its data over time and I haven't found a source for the code to reprogramme it.

[skote]

Originally Posted by elginseam

The SIMMs on a Nexus must be installed in pairs starting with the slots nearest the gold edge connector. As the jumpers suggest the only options are 2, 4 or 8MB installed using two or four 1MBx8 SIMMs for 2 or 4MB, and two 4MBx8 SIMMs for 8MB. Since you have 6MB already installed you can only add 2MB using two 1MBx8 SIMMS.
My Nexus card stopped working I think because the EPROM has lost its data over time and I haven't found a source for the code to reprogramme it.

Thanks for the pointer, but I think either the RAM is no good or the board is no good. I now have my HDD working via another controller and I unplugged all my other cards (extra RAM, accelerator etc) when trying the RAM, from the edge first as you say. At least I think I did I tried so many combinations I should have written them all down!