GBA1000 rev4 Build Log

I would have to physically check it again to know exactly which (I'm not near it now) but it was one of these when I checked earlier - I just didn't write it down:

8375: 318069-10
8375: 318069-18
8375: 390544-01

I think one of the first two, but I'm guessing. I really can't remember. It's from a donor A500+ motherboard. I did spot that my A600 should have a compatible one so got all excited for a moment. Then I looked and saw that in the 600 it's soldered, not socketed and there's no way I'd get that off and the 600 survive to tell the story :lol:
 
Just so I can rule it out - what KickStarts work with the GBA-1000 ?

I'm aware of the legalities of obtaining them so not asking for it, but I would like to know that I'm not trying to use one that won't work.

So far I've tried the 3.1 out of my A600, and whatever was in the A500+ donor board (2.04 I think). I do have a 2.04 from the A600 before I upgraded it here somewhere but I'd need to find it and would assume that if that worked then the 3.1 would too so probably no need.
 
uses the single chip ks3.1 should work in the correct slot. I bought mine from vesalia or amigakit.. I think its the A2000/500/600 ks3.1 rom.
 
OK, double checked and that's the one I've been trying. 99% sure I've got a bad Agnus here. I looked at the RAS and CAS lines coming out of it tonight and to say they look suspect is putting it mildly. One minute they've got reasonable activity on them but pulled down really low like theres an internal GND issue in the custom, try again a bit later and I'm seeing a straight forward 3.5Mhz (or so) sine wave on the outputs.

So I need to start from a known good Agnus I think. Shame as it's yet more money but what can ya do :p
 
Hi MartinW,
if you need a 390544-01 Agnus, I still have 2 left. I sold a lot of them here last year. Maybe you have a look on the thread.

Best regards

FD
 
Thanks for pointing that out. I've replied in the thread and PM'd. I should know in the morning if I still need one or not. I'm tempted to pick up a spare but if I don't really need one then it will only be costing me money and preventing someone else from getting one :)
 
OK, my replacement Agnus looks like it's also faulty as there are no CAS signals coming out of this one, so PM has been sent to FD :)
 
Hi,
I got a faulty A1000 mainboard. I am not sure but can I use all external connectors for my GBA board?

As far as I know there are some differences between A500 and A1000 connectors. Maybe I am totally wrong so hope that someone here could say more about this topic :)

Best regards

FD
 
I'm not sure as I haven't ever seen a real A1000 motherboard close up but you should be able to use all the D-Sub connectors, the 4pin keyboard connector and the VGA connector (I think that one's the same) but you'll certainly have to double check the RCA sockets. They're the ones that for me I couldn't use off my A500+, BUT the A500 ones are too big, so maybe the A1k one will be OK :)

Be a bit wary of the 23pin video connector! I had one hell of a job getting that off and essentially had to destroy the A500+ motherboard to do so. And I have good desoldering kit as well! I think there's a lot of pins connected to the ground plane so I guess that's why. For me it just made sure there was no chance of ever getting the A500 going again, but hey, I was pinching all it's chips anyway :P
 
Hi,
I got a faulty A1000 mainboard. I am not sure but can I use all external connectors for my GBA board?

As far as I know there are some differences between A500 and A1000 connectors. Maybe I am totally wrong so hope that someone here could say more about this topic :)

Best regards

FD

The Serial and Parallel ports on A1000 are of different gender (male/female) (compared to other Amiga models)....not sure about the signals...never checked if the gender-changer allows to use them with other 'standard' Amiga (A500, A2000...) hardware that connects to Parellel and Serial ports...

...actually I never looked into it for the GBA1000....which gender is used for the GBA1000 in case of Parallel and Serial ports? The A1000 standard or the 'newer' A500?
 
They're the opposite to A600 / A4000 - I know that much as I spotted it when I was putting mine on. I need to verify that it's OK to do so, but assuming it is, I'm going to swap mine over so they match up with everything else that I have.
 
Drew this up for later in case I needed it. Mostly I just like the ergonomics on the later keyboards better with cursor etc. But it will convert a 5 pin DIN A2000 / A3000 keyboard to the RJ22 A1000 jack.
 

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My GBA is finally alive! (Hooray!)

But with some kind of odd behaviour and I was just wondering if I've got my config options muddled up at all...

With S5 open (boot rom disabled) it won't boot, I just get a black screen. With S5 closed (boot rom enabled) and a BLANK flash rom I first get a guru meditation and then it will boot. Subsequent warm boots are fine with no guru meditation. I was able to go into workbench and program the flash. No fast ram was detected and that was not a big surprise as I've made a bit of a hash of that and it needs to be gone over again.

Once the flash is programmed I can't boot at all with S5 closed or open. But very occasionally, I can trip it up by closing the jumper with the power on and I get the flash animation followed by a normal boot.

So this tells me that my flash ROM can't have any major bridges or anything or it wouldn't program and erase and indeed boot. But I'm a bit stuck as to why I can't get to the kick-start screen normally without the flash rom.

Any ideas?

There are a couple of solder pads near the ROM switch. S4 & S8. Am I meant to do anything with them? I couldn't see any info on them...
 
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Nice. I'm going to start putting mine together this weekend. By the way, the schematics suggest that you should solder IC27 (NE564) directly on the board instead of using a socket.
 
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Does anyone know if the DigiKey BoM has been updated, recently? Last time I looked at it, DigiKey was out of certain filters, and I couldn't find appropriate replacements at any of the other US electronics parts houses.

- Alex
 
Hello fellow freaks! Here's some pics attached from where I'm at now. http://punainen.org/~lemming/gba1000-11-it_is_done.jpghttp://punainen.org/~lemming/gba1000-12-is_it_done.jpg Now trying to breathe, etc, I'm quite extremely delighted by this right now :) drives and stuff will be added after I have my feet back on the ground etc :D (hmm, something is killing my carriage returns, sorry for the shoddy looking post)

They do indeed. In all the pictures I've seen so far everyone has used sockets, and I've not heard anyone complaining yet!

My board is complete and I've been using it a few weeks now. The fast RAM was an absolute bugger and I've got a problem with the RAM from $1400000 to $15FFFFF. Since I don't have any rework kit for SOJ stuff I'm going to have to send my board off to a mate to be looked at. It all works OK if I clear the boot ROM so it doesn't auto-configure and then just add the other 6MB manually (or just disable fast ram entirely) but sadly it runs like a snail if you do that. With that bank of memory enabled it crashes all over the place :(
 
Battery..... the manual/bom says 1200mAh. Isn't that quite overkill? I mean, you can power up a VIC-20 with that much current :)
Could it be some sort of a typo, having an excess 0 there or something. The usual trapdoor expansion clock circuit batteries I remember seeing have been roughly 100mA +-20%..
 
no its correct, you'll find the same batteries in some Apple macs and things. just google it they come in size AA's or half AA's. Most commonly they are 1/2AA size.
 
1200 mAh doesn't refer to current, but capacity. The clock chip actually uses current in the range of micro-amperes (µA) :) The suggested LS14250 is a certain type of very high-capacity lithium battery that should last a long time.
 
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