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-   -   GVP 1230 Turbo+ Jaws Problem (http://eab.abime.net/showthread.php?t=23393)

broddr 20 May 2006 16:00

GVP 1230 Turbo+ Jaws Problem
 
Hey everyone,

I am looking for help in seting up my accelerator card.

I have installed the card in my A1200 but the amiga will not boot at all.

No error screens, the amiga powers up the hard drive spins up but then it just sits with a dark grey screen.

Obviously the amiga boots up with no problem without the card installed so it cannot be a problem with the amiga itself.

The card has jumpers on it and having fiddled with them I have found one combination that allows the amiga to boot, but when it does it does not recognise the card at all.

When I boot with the mouse keys held with the card jumpers in this particular configuration the card diagnostic screen shows no card.

If I set the jumpers how they originally were (and how the photo at bboah shows them) I can't even access the diagnostic screens. This is also the case if I set the jumpers in any one of the millions of configurations I have tried except the one mentioned above.

The guy I bought the card from insists that it is good and keeps insisting that it worked fine in his a1200 last week

I just wanted to know if anyone knows of a jumper config for the card I should be using or indeed if there is something I need to do to the amiga itself to get this damn card working.

Things I have tried:
  • downloaded an adf install disk for the card and installed that
  • tried the stick of ram in both ports
  • tried taking the chips out and trying them in different configurations ie one out, other out, both out etc
  • bent the pins out in the connector to make a better contact with motherboard
  • disconnecting hdd and fdd and trying them one at a time
  • trying the aforementioned jumper configurations
I am going to try and reinstall workbench now to see if that does anything but I can't see it as it looks like purely a hardware problem.

I am new to this amiga game and I am quite happy to admit that I may be doing something wrong but my personal belief right now is I was sold a duff card.

I just wanted to find out if it is me doing something wrong before I go shouting at the guy who sold the card to me and demand my money back.

Thanks in advance for any help anyone can give me.

bRODDR

coze 23 May 2006 15:31

I had a gvp 1230 until a few months ago. Don't bother with the installing workbench, if you can't get the early boot menu, it's definitely a hardware problem. I used mine without any software installation on a stock 3.0 workbench just fine. My advice would be to check the card fits into the expansion slot ok. Also check if the ram sits ok. If these do not work you may try an alcohol shower in case there's something on the board causing a short somewhere. I just recently read a success story with an apollo card working after the bath.

musashi5150 23 May 2006 16:19

I'd like an alcohol shower too.... :D

Spirantho 30 October 2013 08:37

Apologies for the thread necromancy, but this may be useful.

I've been trying to fix an A1200 rev 2b motherboard which doesn't play nicely with my GVP 1230 Turbo+ card, with exactly the same symptoms as above. The card is perfect in my revision 1 board.

What's happening is that the /BOSS line is being asserted (sent low) but the /BR one is being left floating. The /BR is then pulled down to /BOSS by R118 and pulled up by another 1K resistor to 5V, making the voltage of /BR 3V. Obviously this is NOT a TTL level! This makes the 68020 not at all sure if it's the only CPU on the bus, and it tries to run at 40MHZ at the same time as the 68030. Not good.
The jumper setting the OP found disabled the 68030 which is why it worked: /BOSS was set high so /BR was a clean 5V.

The rev 1 boards short /BR to /BOSS so on that board /BR is grounded and the 68020 is safely disabled.

The solution? I reckon just short the /BR and /BOSS line on the accelerator. Going to try it later but I think it'll be fine... it'll just be the same as the rev 1 I'm using. I think maybe GVP were just lazy and only grounded one of the lines to enable it, instead of both (because the pins were shorted anyway on the boards made at the time).

Hope that helps someone some day!

Loedown 30 October 2013 08:53

Quote:

Originally Posted by Spirantho (Post 919356)
Apologies for the thread necromancy, but this may be useful.

I've been trying to fix an A1200 rev 2b motherboard which doesn't play nicely with my GVP 1230 Turbo+ card, with exactly the same symptoms as above. The card is perfect in my revision 1 board.

What's happening is that the /BOSS line is being asserted (sent low) but the /BR one is being left floating. The /BR is then pulled down to /BOSS by R118 and pulled up by another 1K resistor to 5V, making the voltage of /BR 3V. Obviously this is NOT a TTL level! This makes the 68020 not at all sure if it's the only CPU on the bus, and it tries to run at 40MHZ at the same time as the 68030. Not good.
The jumper setting the OP found disabled the 68030 which is why it worked: /BOSS was set high so /BR was a clean 5V.

The rev 1 boards short /BR to /BOSS so on that board /BR is grounded and the 68020 is safely disabled.

The solution? I reckon just short the /BR and /BOSS line on the accelerator. Going to try it later but I think it'll be fine... it'll just be the same as the rev 1 I'm using. I think maybe GVP were just lazy and only grounded one of the lines to enable it, instead of both (because the pins were shorted anyway on the boards made at the time).

Hope that helps someone some day!

A level of 3V will be seen as a logical level high, going from my PIC manuals a logical level 0 is from ground to 0.8V and high is from 2.0V to Vdd or +5V so 3.0 would certainly be high. Although there is a range of ambiguity between low (0-0.8) and high (2.0 - 5.0 ), undetermined (0.8 - 2.0), exactly why schmidt triggers exist.

Spirantho 30 October 2013 09:48

Exactly. 3V tells the 68020 that there's nothing on the bus (same as 5V) but more importantly, what it tells me is that something's wrong.

I just shorted the /BR and /BOSS pins on the accelerator (luckily they're right next to each other) and Bingo! It works perfectly now.


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