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Author Topic: Zorro II or ISA Ethernet card  (Read 13578 times)

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Offline spirantho

Re: Zorro II or ISA Ethernet card
« on: July 10, 2011, 07:50:04 AM »
A couple of points....

I don't think you can run an Amiga Ethernet card from the Pc side, but you can do it the other way round. Would be interesting if I'm wrong though!

I do know however, that you cannot use a sound card for a hard disk. Not only is the bus not standard IDE (they'd not standardised ATAPI yet) but the BIOS wouldn't understand it anyway.

Nice setup though - you found a SL3 chip!
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!
 

Offline spirantho

Re: Zorro II or ISA Ethernet card
« Reply #1 on: July 13, 2011, 09:26:37 PM »
Quote from: Jeff;649310
Some company also too the A2386SX, and removed the 386 chip and soldered a 486 in place. I think they sold a few like that but I have never seen one. Since the clip on upgrades work so well I never had the nerve to try this.


I have that board. It's by Elite Micro Systems and it has a 486Slc at 33MHz.
I paid good money for it in 1995 and it never worked, try as I might, alas.
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!
 

Offline spirantho

Re: Zorro II or ISA Ethernet card
« Reply #2 on: July 13, 2011, 11:06:05 PM »
Bogus isn't the word.
£350 that card cost me in 1995 - I was a student. I waited impatiently for 6 weeks for it to arrive from the States. When it finally came, I plugged it in... ran the install disk.. rebooted... "Cannot open janus.library".

That's all I ever got.

Eventually I found that it had a bad bit of dual-ported RAM, but this was after several other attempts at fixing things. I think the 74LS74 was bad too - it wasn't autoconfiguring.
My brother and I had a go at fixing the RAM by soldering in one of the other RAM chips. We didn't know in those days that the main RAM was static column, not Page Mode (we didn't know there were two types of Zip RAM!).

About 4 years ago, I finally twigged that it had had the wrong RAM in it all these years after we tried to fix it. Since that attempt I'd got hold of another A2386SX and had been switching chips to track down bad ones. One of the chips - a 74ACTQ244 - died on the operating table (lost a leg). Typically enough, this is an incredibly hard to find chip. Hence the chip socket on the board that's not filled (my '244 is in my working 2386SX).

Since those days I've managed to track down four new 41464AZ08 Zip RAM chips (that was no easy task, I can tell you).

These boards are very difficult to desolder on without lifting tracks - that's why there's lot of wires added on. Most of the wires in the photos are to make sure of bad contacts caused by IC sockets and chips where lifting the chip took the track with it.

Unfortunately no-one ever came up with a schematic... would have been more than useful.

Every now and again I take another crack at this board to try and sort it. It's more of a principle now.... even though my A2386SX is faster (it has a 486SLC2/50 on) and I have a 486SLC GoldenGate, I still want this board to work.

I really need another A2386SX for parts, so I can get a good 74ACTQ244. Incidentally, I do actually have some of those chips - but they're SMT. I bought them just in case they come in handy and I find some way of reliably soldering one into a DIP package!

My next task I feel is to remove all the IC sockets, and do a high resolution scan of both sides of the board. Then I can identify any dodgy-looking contacts and check them with the multimeter. Once that's done I can solder in known good chips to get it as close to original as possible, and try again - I have rather more experience of these things now (just completely re-capacitored my A2000 a few days ago, for example)!

By the way, don't suppose anyone has any 74ACTQ244 chips handy, do they...? :)
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!
 

Offline spirantho

Re: Zorro II or ISA Ethernet card
« Reply #3 on: July 14, 2011, 09:39:15 AM »
@Zac67
"Q" stands for "Quiet". Not tried a simple F, might work - if unreliably. Maybe I'll try sticking an F into my working 386.

@J-Golden
Most of the chips have been taken out and re-inserted. It's not just a seating issue. If a chip's coming out I just didn't put it fully back in again.

@Motormouth
Look more closely at the bridgeboard. :) Not all the ZIPs are socketed (wish they were)!

Going to try and source a 74F244 now... OK. Got 10 of them, will try it tomorrow in my 386.

Would be fabulous if I can get this baby running after all this time, but I'm not going to hold my breath. If anyone can help though that'd be fantastic, but I don't think there's much anyone can do over the net (unless someone has the schematics PLEASE :) )
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!
 

Offline spirantho

Re: Zorro II or ISA Ethernet card
« Reply #4 on: July 14, 2011, 09:53:11 AM »
Incidentally, how many of these boards have ever been seen? I never came across another.... I guess they're pretty rare!
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!
 

Offline spirantho

Re: Zorro II or ISA Ethernet card
« Reply #5 on: July 14, 2011, 10:10:16 AM »
I don't remember seeing other 486 ones though....?
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!
 

Offline spirantho

Re: Zorro II or ISA Ethernet card
« Reply #6 on: July 15, 2011, 08:53:02 PM »
Thanks for the encouragement. :)

Today I removed all the IC sockets, and checked all the ICs that are socketed to make sure they're good.
I found that the 74LS74 was dubious so that's gone. I also noticed several tracks not reaching the pins of the IC sockets.
I've now taken hi-res photos of the board where the sockets are, and replaced the chips.  I plugged the board in and tested the memory and everything came up as zeroes, so RAM access is still dead, but the board is autoconfiguring correctly at address $200000, and is recognised ok as an A2386SX.

I've mapped out the connections from five of the ICs now, and verified them. Next step is to check the connections of the other seven or so from the photographs. Could be a while!
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!
 

Offline spirantho

Re: Zorro II or ISA Ethernet card
« Reply #7 on: July 19, 2011, 11:41:41 AM »
"something" being a Goldengate II or a Commodore bridgeboard. I think a 2286 may work, but not sure.

Incidentally, for those who are interested.... About an hour ago I got RAM access on my 486 BB! Every time since, though, it's gone back to crashing before initialising when running Binddrivers (i.e. no memory access). GARGH.
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!
 

Offline spirantho

Re: Zorro II or ISA Ethernet card
« Reply #8 on: July 19, 2011, 12:41:42 PM »
Quote from: J-Golden;650552
That great!  I know it's not fully functional yet, but your are getting closer and closer.  KEEP IT UP!!!:)


Yes, I'm encouraged by the fact that I got some memory access, even if it was only 4 bits that were correct!

But I can't get it to happen again! *sob*.

At least now it doesn't hang solid, it just guru's instead (7fffffff.48454C50 - that's ASCII for HELP by the way!). It even occasionally opens janus.library successfully... though of course nothing happens because the RAM isn't talking for some crazy reason.
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!
 

Offline spirantho

Re: Zorro II or ISA Ethernet card
« Reply #9 on: July 19, 2011, 01:14:12 PM »
Quote from: psxphill;650556
There was a cheap card that had no pc emulation on that allowed isa boards to be used from amigaos. It came with drivers for the usual suspects. From memory the hardware is pretty trivial, it's basically a handful of chips so it can be autoconfig'd and some buffers so the bus can be tristated.
 
It should be very easy for someone to make them.


Yes, that's the GoldenGate II. The GoldenGate I was an emulator board, the GG-II just a bridge to the ISA slots. You could use NE2000 cards and things, but AFAIK there was never an RTG graphics driver made.
--
Ian Gledhill
ian.gledhill@btinternit.com (except it should be internEt of course...!)
Check out my shop! http://www.mutant-caterpillar.co.uk/shop/ - for 8-bit (and soon 16-bit) goodness!