BloodyCactus
Member
confirm what? the lsi is not optional, it must be programmed. All I know it does things with the memory addressing system / RAM.
GBA1000 rev4 Build Log
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confirm what? the lsi is not optional, it must be programmed. All I know it does things with the memory addressing system / RAM.
Ok i'll rephrase. Can someone confirm that if the lsi is not programmed, there are chances that the screen will stay black when gba1000 is powered up.
Thank you.
I will check for you and let you know
I can confirm you will get a blank screen without the lsi1024
Does anyone know - FOR SURE the kind of Flash Chip that is required for this project please?
I know it needs to be 29F800 TSOP48 because the schematics say as much. I've seen 90ns and 70ns listed in parts lists so I would assume that the faster 70ns would be OK. But there are two variants. BT and BB. The difference is where the boot sector is located, top or bottom. The idea is one will boot from 00 the other from FF (in probably over-simplified terms).
SO, I know when Kipper supplied the PCBs he offered to supply, program and fit this chip. And I know he fitted the BT-90ns variant (why the original buyer of my PCB didn't go for that, I don't really know
). What I have no way to know is whether that was just because it was what he could get at the time, or whether it HAS to be the BT variant to work??
Since I have been offered a 29F800-70BB, I would like to know if anyone has a GBA-1000 up and running using the BB (bottom boot) variety or if I have to continue to search for a BT variant. I really, really don't want to fit the wrong one and replace it later. That would be a nightmare.
Thanks,
Martin.
I know it needs to be 29F800 TSOP48 because the schematics say as much. I've seen 90ns and 70ns listed in parts lists so I would assume that the faster 70ns would be OK. But there are two variants. BT and BB. The difference is where the boot sector is located, top or bottom. The idea is one will boot from 00 the other from FF (in probably over-simplified terms).
SO, I know when Kipper supplied the PCBs he offered to supply, program and fit this chip. And I know he fitted the BT-90ns variant (why the original buyer of my PCB didn't go for that, I don't really know
). What I have no way to know is whether that was just because it was what he could get at the time, or whether it HAS to be the BT variant to work??Since I have been offered a 29F800-70BB, I would like to know if anyone has a GBA-1000 up and running using the BB (bottom boot) variety or if I have to continue to search for a BT variant. I really, really don't want to fit the wrong one and replace it later. That would be a nightmare.
Thanks,
Martin.
BloodyCactus
Member
I dont think it matters. People have working boards that have the 90ns kipper put on them. I know from pics Hesse who made the previous revision has a 70ns chip.
from pics, Hese's board has a 70ns BB chip. I dont know for sure the variant kipper put on our boards.
BloodyCactus
Member
you'll have to ask someone like yamakakiche who has a working board if kipper put his chip on, and if its a 90ns BT or BB chip...
I think you might be slightly missing my point here 
I already know someone who has a working board, which originated from Kipper and Kipper had put on a 29F800BT-90. So I know that works.
If you're saying that Hese has a working board with a 29F800BB-70 then that's good for me and I'll pick up the part I've been offered
I already know someone who has a working board, which originated from Kipper and Kipper had put on a 29F800BT-90. So I know that works.
If you're saying that Hese has a working board with a 29F800BB-70 then that's good for me and I'll pick up the part I've been offered
BloodyCactus
Member
as long as you understand he has a working rev1 board instead of a rev4 board.
see here, halfway down the page closeup of the TSOP.
https://www.amibay.com/showthread.php?t=45005
see here, halfway down the page closeup of the TSOP.
https://www.amibay.com/showthread.php?t=45005
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OK, cool. Understood that it's the Rev. 1 board in the picture.
I've been over the design, the schematics and also the data sheet for the FRAM and to be honest, I'd pretty much come to the conclusion with the way that the chip is wired up in the design that it should be OK. The picture from that thread pretty much confirms it but it certainly gives me enough confidence to go for it.
Checking through the change log there has been nothing as fundamental as to affect the variant of the FRAM used between v1 and v4 of the board.
I will of course update when I have a working or non working completed board. Right now I have everything except an Amber (optional but I certainly DO want one), the fast RAM chips (still on the slow boat over) and this FRAM.
I've been over the design, the schematics and also the data sheet for the FRAM and to be honest, I'd pretty much come to the conclusion with the way that the chip is wired up in the design that it should be OK. The picture from that thread pretty much confirms it but it certainly gives me enough confidence to go for it.
Checking through the change log there has been nothing as fundamental as to affect the variant of the FRAM used between v1 and v4 of the board.
I will of course update when I have a working or non working completed board. Right now I have everything except an Amber (optional but I certainly DO want one), the fast RAM chips (still on the slow boat over) and this FRAM.
Screen weirdness on GBA1000v4
Screen weirdness on GBA1000v4
Hi Guys,
Just finished assembling my GBA1000v4 Board, got all the GALs and the ISP1024 programmed but something with the video seems messed up.
Video gets initialized and after a bit it looks like its trying to display something (but the lines seem to be scrambled). After a few secs the screen goes blank again and after roughly 10-15 secs the process starts again. Scope on the composite output shows activity during this time.
Swapping Denise, Agnus, 8520's and the ISP1024 didn't have any effect, but removing Agnus/ISP1024 completely, yields the expected black screen that just has the sync signals so I'd guess that Agnus and ISP1024 are doing their job. I Couldn't swap Gary since i only got one atm.
Unfortunately i also only have a Kick 1.3 Rom atm so I'm not sure if that's the reason for the weird behaviour :-(. Next step will be to trace the Chipmem connections, but after that I'm fresh out of ideas.
Did any any of you have had a similar problem? Any tips would be greatly appreciated.
Thanks,
Johannes
p.s.: I'm debugging under the assumption that the fast mem chips, the IDE part and the flickerfixer part are not essential so couldn't cause this behaviour, please correct me if I'm wrong.
Screen weirdness on GBA1000v4
Hi Guys,
Just finished assembling my GBA1000v4 Board, got all the GALs and the ISP1024 programmed but something with the video seems messed up.
Video gets initialized and after a bit it looks like its trying to display something (but the lines seem to be scrambled). After a few secs the screen goes blank again and after roughly 10-15 secs the process starts again. Scope on the composite output shows activity during this time.
Swapping Denise, Agnus, 8520's and the ISP1024 didn't have any effect, but removing Agnus/ISP1024 completely, yields the expected black screen that just has the sync signals so I'd guess that Agnus and ISP1024 are doing their job. I Couldn't swap Gary since i only got one atm.
Unfortunately i also only have a Kick 1.3 Rom atm so I'm not sure if that's the reason for the weird behaviour :-(. Next step will be to trace the Chipmem connections, but after that I'm fresh out of ideas.
Did any any of you have had a similar problem? Any tips would be greatly appreciated.
Thanks,
Johannes
p.s.: I'm debugging under the assumption that the fast mem chips, the IDE part and the flickerfixer part are not essential so couldn't cause this behaviour, please correct me if I'm wrong.
The google translation for the bottom entry in that document (the SV3 VGA jumpers) has a note that reads:
What does that mean? I'm not 100% sure on how the flicker fixer works at all but I think it's saying that by closing the rest of the links the standard flicker fixed / scan doubled signal will be passed through to the VGA cable (for use with a multi-sync monitor), but (assuming that's right!) I'm not sure about the last bit with the two grounds. Not sure under which circumstances you would close them or leave them open.
What does that mean? I'm not 100% sure on how the flicker fixer works at all but I think it's saying that by closing the rest of the links the standard flicker fixed / scan doubled signal will be passed through to the VGA cable (for use with a multi-sync monitor), but (assuming that's right!) I'm not sure about the last bit with the two grounds. Not sure under which circumstances you would close them or leave them open.
According to the Board and the Layout 1-2 and 9-10 are already connected to GND so no need to close them with jumpers. All the pictures of finished boards show them not closed as well.
---------- Post added at 15:32 ---------- Previous post was at 14:18 ----------
I already tried that before to see if it changes anything, but no, same behaviour either way. (The A1000 PSU that i use definately works as well, had it running with the original A1000 Board before i put in the GBA one).
Sadly, my build has now come to a grinding halt. Well, pretty much.
All I have left to add is the 29F800 when it arrives from China and I'm half way through the fast RAM. I'm finely them particularly hard and time consuming so I took a break from them last night to get everything else programmed up and completed.
Unfortunately, with all the GALs programmed, the LSI programmed and everything in place all I get is the briefest of graphical flash up on the screen and then nothing. Looking at the activity on the KS ROM I'd say it starts to boot and then fails and locks up.
I didn't have the luxury of starting off from a known good set of customs so from looking at general troubleshooting tips on Amigas it looks like my Agnus could be bad. I guess I have no way to know until I can find another one to buy and swap it out. Unfortunately I don't have any spare that are not soldered directly to good working machines.
Is my assumption likely correct?
I'm also working on the assumption that the fact I have not finished all the fast RAM would not prevent the machine getting to the KS screen, though later in the week I'll finish putting that on anyway...
All I have left to add is the 29F800 when it arrives from China and I'm half way through the fast RAM. I'm finely them particularly hard and time consuming so I took a break from them last night to get everything else programmed up and completed.
Unfortunately, with all the GALs programmed, the LSI programmed and everything in place all I get is the briefest of graphical flash up on the screen and then nothing. Looking at the activity on the KS ROM I'd say it starts to boot and then fails and locks up.
I didn't have the luxury of starting off from a known good set of customs so from looking at general troubleshooting tips on Amigas it looks like my Agnus could be bad. I guess I have no way to know until I can find another one to buy and swap it out. Unfortunately I don't have any spare that are not soldered directly to good working machines.
Is my assumption likely correct?
I'm also working on the assumption that the fact I have not finished all the fast RAM would not prevent the machine getting to the KS screen, though later in the week I'll finish putting that on anyway...
BloodyCactus
Member
could be your agnus. depends on which version you have.
