GBA1000 Build Project

hese

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AmiBayer
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I have been working on this GBA1000 rev1 board for some time now. I thought to share with you this project as I finally received all the missing parts to complete this. (took a couple of months to source a working LSI1024 but that's another story...)

The board assembling was done a bit backwards, as most of the connectors and sockets were soldered first. (not the best move...)


Soldering the SMD resistors, capacitors etc. near the connectors got a bit trickier now.


Had to be careful not to torch the plastics.


After the SMD parts had arrived I began to solder the tiny resistors, capacitors, beads etc. to the board using a temperature controlled iron with chisel tip.


It took a couple of days to solder those SMDs. It would have been easier and faster to use a hot air gun but didn't want to risk melting the plastics near the parts.


Next it was the time to solder the FAST ram chips.


Nothing special really, took a couple of hours to put them in place.


Soldering the TSOP chip was the toughest one but it was quite simple in the end really.


What I did was I first soldered one leg of each corner of the chip to the board just to keep it in place. Then I put a plenty of liquid flux on the legs and a small bit of solder to the chisel tip. After that I just touched the legs with the tip to solder them. None of the legs got short circuited thanks to the flux. It took about a minute to solder one side of the chip. The other side was a bit harder because the sockets were in the way.


After soldering some random missing parts, the board was almost ready. The next step was to program the GAL chips and the LSI1024 using an eprommer.

Only the Boot ROM (TSOP chip) doesn't need to be programmed beforehand. You program it when the board is running.


After programming the chips, the old Amiga 1000 motherboard was replaced with the new GBA1000. For the mass storage I used a Compact Flash card connected to the 44 pin IDE connector.


I switched the power on but did it work?

Yes sir, it sure did. First took a quick SysInfo test.


The FAST memory was allocated in the 24bit area.


In order to get the FAST memory to the 32bit area, you have to program the Boot ROM using the software found on the Georg Braun's website. Below you see the files you need for programming the ROM.

First I erased the ROM using erase_flash tool. Then I wrote the program using GB_A1k_8MB_RAM command.


After programming I connected a jumper to the S5 switch in order to activate the Boot ROM.


Ran the SysInfo to check the changes.


The last thing to do was building the DIN-VGA connector for the monitor. Here's the connection diagram.


Don't forget to short the RGB, HSYNC and VSYNC pins on the SV3 connector to allow signals pass from the flicker fixer to the DIN connector. I used jumpers for this.



Some things to note about building the board:

  • You don't really need any special soldering tools to build this. A plain temperature controlled iron with chisel tip, some solder and solder flux is enough.
    That's what I used. If you want to save (much) time you could use a hot air gun to solder the SMD parts.
  • Solder the tiny SMDs first to save yourself from additional trouble. (doh.. :picard)
  • It takes roughly a week to build the board. Spare two three days for soldering the SMD parts (capacitors, resistors, ...),
    a day or two for soldering the sockets, connectors and the rest. And a day for programming the chips and testing the board.

This was an interesting project. I wish you well with your GBA1000 board projects, there should be a flock of new boards coming soon..
 
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Nice work (y)

Thanks for sharing :)
 
I think GBA1000 is such a GREAT piece of hardware, I'd like to get one too for my A1000 but unfortunately I haven't time at all for assembling components... :unsure:

Anyway, I really like your job! Enjoy it! (y)
 
Great to see your work. I'm sure your pics and advice will help a lot :)
 
Nice work hese, and thanks for sharing :)

My board and ICs should be heading over the atlantic sometime soon, so I'm starting to plan how to get all the remaining bits I need and working out the order to go a this, so good to see how you've approached this.

Did you have a donor A500+ / similar or source the components from an electrical outlet / ebay?
 
I can't believe that it worked first time you turn it on!
I ordered the board, just like many of us, and I can't wait to doing it myself.
It looks like the best way to start the work is to begin with the smallest parts, like SMD resistors and capacitors, and work your way to the bigger parts.
 
what programmer did you use for the LSI1024?
I used Wellon VP-490 for programming the chips.

If you want to save some money, you could build a JTAG adapter and use the free Lattice ispLEVER Classic software to burn the LSI1024.

---------- Post added at 14:45 ---------- Previous post was at 14:44 ----------

I think GBA1000 is such a GREAT piece of hardware, I'd like to get one too for my A1000 but unfortunately I haven't time at all for assembling components...
If you ever get a blank GBA1000 PCB, I can assembly the board for you.

---------- Post added at 14:49 ---------- Previous post was at 14:45 ----------

Did you have a donor A500+ / similar or source the components from an electrical outlet / ebay?
I had a spare A500 for some odd parts but almost everything I bought new from various electrical outlets such as Mouser, Reichelt and Elpro.
Fat Agnus, Amber and video hybrids I bought from eBay.

---------- Post added at 14:56 ---------- Previous post was at 14:49 ----------

I can't believe that it worked first time you turn it on!
It looks like the best way to start the work is to begin with the smallest parts, like SMD resistors and capacitors, and work your way to the bigger parts.
I was slightly surprised to see it run on the first try.

I recommend to solder the surface mounted parts first before continuing to through-hole parts. Otherwise it gets crowded.

---------- Post added at 15:04 ---------- Previous post was at 14:56 ----------

Very sexy board pronage there my friend :D
Pronage? W0t, are you talking dirty with me :p
 
i was a bit tempted by this board as i actually have most of the components here for the build.

its a really nice looking board indeed congrats.:)
 
Thanks guys.

Added a couple of pictures of the DIN-VGA connector.
 
Excellent work! Lovely to see another of these boards working!

But one question: does your Audio and Composite video work? I read a comment from Georg somewhere that the coloured connectors do not work: even worse they cause a short circuit when something is connected. You cannot use the Same connectors as in the Amiga 600/1200 but you can use them from an A500.
 
But one question: does your Audio and Composite video work? I read a comment from Georg somewhere that the coloured connectors do not work: even worse they cause a short circuit when something is connected. You cannot use the Same connectors as in the Amiga 600/1200 but you can use them from an A500.
I haven't tried the composite video nor audio but will test them and report back.
If I recall correctly the problem was with the polarity of the connector (signal and ground were mixed).
 
The colored RCA connectors I used had reverse pinout (signal pin -> gnd on mobo, gnd pin -> signal on mobo) so they needed to be replaced (good catch, Tahoe).

Here a picture of the RCA connector with correct pinout and after soldered in place. Tested the audio and now it works fine.
 
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