Amiga 3000D resurrection

[DarrenHD]

Originally Posted by Jope

If you intend to use the rear sockets U182 and U183, you should order 27C220. If you intend to use the front sockets U180 and U181 or plug the chips into a ROM tower, it is 27C400.

If you want to stop using the tower, you can do this and order 27C220 chips, leave out the tower and plug the chips into U182 and U183 on the motherboard.

If your system shipped with the rom tower, the motherboard U180 and U181 are wired incorrectly and you shouldn't plug any chips in there.

Jope, you are spot on. I ordered a bunch of 27C220 EPROMS for my A3000 early revision 6.1 (anyone need to buy any? My A3000 came with no ROM Tower - only 27C220 ROMS in the rear two rom sockets. any ROMS you buy from dealers won't work, you will need to burn your own 27C220 roms to put in those sockets. You can't find ROM towers to buy anywhere.

[DarrenHD]

Originally Posted by Jope

If you intend to use the rear sockets U182 and U183, you should order 27C220. If you intend to use the front sockets U180 and U181 or plug the chips into a ROM tower, it is 27C400.

If you want to stop using the tower, you can do this and order 27C220 chips, leave out the tower and plug the chips into U182 and U183 on the motherboard.

If your system shipped with the rom tower, the motherboard U180 and U181 are wired incorrectly and you shouldn't plug any chips in there.

By the way Jope, do you know which ROM goes in U182 and which goes in U183? The 3.1.4 ROMS are named "Lo" and "Hi" on the Hyperion download page. I assume "HI" is U183?

Darren

[quantum8]

According to a post on the hyperion forums it's:
U183 (Lo) & U182 (High)

[DarrenHD]

Originally Posted by quantum8

According to a post on the hyperion forums it's:
U183 (Lo) & U182 (High)

Well that is logical, lol! Thanks for the info.

[Hewitson]

Originally Posted by DarrenHD

Well that is logical, lol! Thanks for the info.

It's not really illogical either. The "hi" and "lo" refers to the data bits in the roms and has nothing to do with the location of the chips on the board.

[Worfje]

Originally Posted by alexh

One tip about A3000 ROM upgrades... no matter which ones you order you'll almost certainly order the wrong pinout first time. There are two pinouts for A3000 and something called a ROM Tower which switches from one to the other. You really want to get ones which work with your motherboard without a ROM Tower as it gets in the way of other expansions you might want in the future.

Thanks for the tip!

I was not aware of the different possible possibilities

I ordered the ROM 3.X Amiga 3000/3000T (two chips) from Cloanto here.

The 'more info' part on the website of Amigastore.eu states nothing about which type of ROMs they are actually selling. The 'installation guide' delivered together with the ROMs does state that the ROMs need to be installed in U180 and U181 (thereby replacing the existing/installed ROMs, in my case).

[Worfje]

I am also working one a replacement case for converting the Amiga 3000D into a 3000T look-a-like:

[Worfje]

Finalized the placement and mounting of the main parts (main PCB, daughterboard, cdrom, disk drive, hard drive(s) and fans:

[Worfje]

The original PSU of my Amiga 3000 states:

Input:
240V 2A 50Hz

Output:
5V 17.25A
12V 3A
5V (user) 0.75A
5V (video) 0.75A
-5V 0.2A
-12V 0.3A

Some old ATX PSU 300W Fortron/Source, Model FSP300-60GT:

Input:
200-240V 5A 50Hz

Output:
3.3V 14A
5V 30A
12V 12A
+5Vsb 0.85A
-5V 0.3A
-12V 1A

AOpen Model FSP350-60PN(PF):

Input:
230V 5A 50Hz

Output:
3.3V 28A
5V 30A
12V 16A
+5Vsb 2A
-5V 0.3A
-12V 0.8A

Chieftec Model HPC-360-202:

Input:
230 5A

Output:
3.3V 35A
5V 35A
12V 17A
+5Vsb 2A
-5V 0.3A
-12V 0.8A

Schematic of Amiga 3000 power supply connector:


Some interesting information here.

Female connector Molex 3901-2201 for connecting the male ATX connector to.
Male connector AMP 172171-1 for connecting conversion cable to Amiga 3000 motherboard.

[Worfje]

I bought the following from part from Conrad to make my own ATX (20pin) to Amiga 3000D conversion cable:

1404056 Renkforce ATX adapter 20pin to 24pin (only to use the 20pin female side)
747817 TE Connectivity Universal-MATE-N-LOK connector 15 pins (172171-1)
749804 TE Connectivity Mini-Universal MATE-N-LOK Power Contact (170366-1)



I needed to add a wire on pin 18 of the 20pin ATX connector to enable -5V.
The +3.3V wires, +5VSB, 'power ok' and one ground wire had no use and have been removed.
I also replaced the +12V wire since it where two wires connected into a single pin, which is not usefull later on when connecting to the mate-n-lok connector. So, I used a single wire which was left due to removing all the +3.3V wires.



Now I have to wait for the TE crimp tool to arrive...

[Worfje]

I made some progress.

I 'recapped' the main board and the daughter board. It took me around 10 hours. I do not have the tools to pre-heat the PCB and removing the ground side of the capacitors was at edge of the capability of the soldering iron I am using (Toolcraft ST-80, 80W) and/or my skills. I used a big tip (roughly 3 mm diameter), but still I had to set the temperature beyond the recommended value of 700 F / 370 C. Still, no visible damage made to the PCB and no de-lamination. Some capacitors (like C168 on the rev 9.02 main board) are connected to two ground planes without thermal relief provisions and as a last resort I drilled out the remaining solder from the via. Sounds sketchy? I really love my Essenbach 118210 on these occasions.

I cleaned the board a bit with an ESD proof brush.

I soldered on an adaptor for CR2032 lithium batteries. This provides backup of the date and time again. The damage that all those barrel batteries made, the horror!





The Makerbeam XL parts came in and if you already used to metric screws it is very nice to work with. The aluminium plates were delivered and now I can adjust them.

[Worfje]

Another practical problem with 4-player games is the relative short wiring between my Arcade joysticks and the Amiga, so I will make a small box to which all 4 joystick can be connected. The small box connects to a 2 meter cable which also connects to the towerized Amiga. I started layouting multiple PCBs that will allow to connect 4 joysticks, show the power led and harddisk activity led (combining the SCSI and Buddha IDE activity led) and a button to turn on the Amiga (hmmm, maybe add a reset button?). The PCBs will incorporate the available 4-player adapter functionality (exploiting the parallel port) and the autoswitching functionality between mouse and joystick connected to port 1.

[trixster]

Enjoying reading this, keep it up!

[Worfje]

Thanks for that response, very nice to read.

The TE crimp tool came in and worked flawlessly, so I would be able finish my ATX PSU to Amiga 3000 connector cable...

But, I was triggered by the existence of +VID and +5V_USER supplies coming from to PSU. The adapter sold by Amigakit.com shows no additional regulators. The adapter by Ian Stedman (which by the way has suspended its sales for some reason) does have a regulator for the -5V, but only since modern ATX power supplies do not supply -5 V. Ian also has a very detailed and impressive webpage on ATX power supplies and how they can be matched to work with different Amiga versions. His choice on handling with +VID and +5V_USER is practical / straightforward: just connect them to the +5V coming from the ATX PSU.

I took a look at the Amiga 3000 schematics (very nice redrawn and available here) to see which parts are using the +VID and +5V_USER.
The +VID connects to ICs VIDIOT (nice name), NE564 (PLL) and AMBER. So, in short all the analogue video related parts.
The +5V_USER is available on the VIDEO OUT (23-pins, 15 kHz), mouse/joystick ports and several other connectors.

For me it was clear that the reason for having a +5V_USER (and not having it connected to +5V) is making the Amiga less prone to errors (electrical shortcuts) made by connected peripherals. I wont follow Ian's advice on connecting +5V_USER to +5V.

I send a message to Dave Haynie (his name was on the schematics, with date 29-Aug-1989, that is some 30 years ago) and he responded 'You really don't want digital noise to get into analog circuits if you can help it. So +VID is an isolated supply for the analog video circuitry.'. I really appreciated the answer. Later I found out that Dave is very active on social media and is giving Amiga related interviews up till date.

I asked him what he meant with isolated, since I know that that often reverts to a supply which has both the supply and ground separated from other supplies and from the Amiga 3000 schematics all supplies seem to share the same ground.
He did not answer and I screwed open the original PSU to see if I could find the answer there and I did. The original PSU holds 4 linear voltage regulators: 7912C for -12 V, 7905C for -5V and two 7805C for +VID and +5V_USER. The ground of all these supplies is one well connected area of vias for all 5 ground wires of the power connector to the main board. Again, I won't follow the advice to connect the +VID to +5V, but I will use additional linear voltage regulators.

[Pyromania]

I enjoy reading this too.

[dalek]

I doubt you will notice any difference with Ian's adapter and 5V coming from the same rail on an ATX PSU. If you are worried, get an ATX PSU that has multiple 5V rails (e.g. labelled 5V1 and 5V2).

[Pyromania]

Has anyone resurrected and used an Amiga 3000+?

[DarrenHD]

Originally Posted by Pyromania

Has anyone resurrected and used an Amiga 3000+?

Over on a1k.org Scrat and Matze got ahold of 5 original AA3000 boards (not sure how). They have built two of them. They are revision 2. Pretty amazing stuff:

https://www.a1k.org/forum/index.php?threads/66906/

For me as a mere mortal I just went with hese's AA3000+ re-creation as it includes a flicker fixer and simm ram. Not the same as an original but still very nice nontheless.

Darren

[Worfje]

The main (and daughter) board have been mounted onto a 3 mm thick plate of aluminium with 12 mm 'spacer studs' (Wurth 970120324). This assembly is now placed in the Makerbeam XL structure.



I started on the IO shield back plate, but the plate thickness was 1.15 mm and together with a 2 mm plate it did not fit into the Makerbeam XL structure which has openings of 3 mm. A plate with the correct thickness has been received.

I reversed engineered an auto-switch mouse/joystick PCB which was made by Ashcom Design and Developments. Doing some searching on the internet showed that this was a company based in the UK and that the Ashcom was a trading name for Ashby Computers and Graphics Limited. The company was dissolved in 19-Nov-2002. It also used the trading name Ultimate Play the Game and was owned by Tim and Chris Stamper. They also sold various memory expansion and hard disk solutions for the Amiga 500. More information on their companies can be found here. Some more information on how their career path followed [ Show youtube player ]. Impressive.

[hese]

Originally Posted by DarrenHD

Over on a1k.org Scrat and Matze got ahold of 5 original AA3000 boards (not sure how). They have built two of them. They are revision 2. Pretty amazing stuff:

https://www.a1k.org/forum/index.php?threads/66906/

For me as a mere mortal I just went with hese's AA3000+ re-creation as it includes a flicker fixer and simm ram. Not the same as an original but still very nice nontheless.

Darren

Yes, not the same. AA3000+ offers everything that AA3000 does and then some more.