Amiga 2000 Rev 6 to Rev 6.2 (or 6.3) hardware changes

[amigasith]

Cheers, folks!I recently got hold of an Amiga 2000 Rev 6 board that really needs some love There is no 6.2 or 6.3 sticker on it and it also still has the RP900 and RP901 resistor packs close to the 68000, so I believe it's either a plain Rev 6.0 or 6.1.

Does anyone know what hardware changes are required in order to turn this board into a Rev 6.2 or Rev 6.3? I'm not only talking about the changes to the custom ICs (Hires Denise, Kickstart 2.04, etc.). Those changes are pretty obvious - I am also looking for things like adding or removing or changing components like capacitors, resistor (packs), etc.

I have really done quite some research now, but haven't found a complete overview yet

The closest I have found are the following links:
- http://www.amiga.org/forums/showthread.php?t=40125
- http://www.homecomputermuseum.de/amirep/a2000.htm (in German)
- http://www.amigawiki.org/doku.php?id...2000_mainboard (in German)
- http://groups.google.com/forum/#!top...re/Ck_FMmk9Nqo (in German)

So please, if anybody has a more complete list of things that have to be changed, I would be very happy

[Jope]

http://www.thule.no/haynie/systems/a...s/rev6_fix.txt

[amigasith]

Originally Posted by Jope

http://www.thule.no/haynie/systems/a...s/rev6_fix.txt

Thanks, Jope However, this is pretty much exactly the same compared to the proposed changes in my first link above... Anyway, thanks for having a look!

Anyone else has other / more descriptions?

[cpiac64]

i have a rev6 with rom tower and a rev6.4, can help you?

[amigasith]

Originally Posted by cpiac64

i have a rev6 with rom tower and a rev6.4, can help you?

Sounds great, thank you very much It would be a bit overkill to ask you to do a comparison component-by-component of the 2 boards, but if you could verify if the following list of changes was really performed on later Rev 6 boards or not, this would be great:

Production Changes:
Delete RP901 and RP902.
Insert resistor packs along side of U603 and U604 before wave solder.
Change value of RP604 to 470 Ohm
Change value of RP903 and RP908 to 1K Ohm
Change value of R1000, R917 and R111 to 680 Ohm.
Change value of RP101 to 2.7 K ohm.

The reason why I am asking for the verification is because this list seems to come from a Commodore internal (?) email that has as a subject

Subject: A2000 Rev 6 rework instructions (tentative)

So this tells me that it's just a proposal, but not a definite production change list.

[amigasith]

Okay so I did a little homework to make life easier for potential supporters of my little project here

I took the best photo I could find from a Rev 6.2 board (hope the guys from BBOAH don't mind) and marked all the places that have been changed from Rev 6 to Rev 6.2. Interestingly enough, I found some more things that were changed from Rev 6 - on top of the above mentioned things. See yourself:



I found what I marked as "funky bridge", a bridge that consists of a resistor and a capacitor between FB906 and a solder pad below the floppy connector. Next, I found what I marked with "extra resistor" - which in reality is R215 removed, and a new resistor soldered from the right solder pad of R215 to a solder pad between the PCB marks for EMI310 and EMI301. Last but not least, C909 was removed in Rev 6.2.

So please, can anybody confirm or refute the following:

1.) Is the value of the resistor packs soldered to U603 and U604 - what I marked with "new resistor packs" - really 2.7K Ohm?
2.) Is the value of resistor pack RP604 really 470 Ohm?
3.) Is the value of resistor packs RP903 and RP908 really 1K Ohm?
4.) Is the value of resistors R1000, R917 and R111 really 680 Ohm?
5.) Is the value of resistor pack RP101 really 2.7K Ohm?
6.) What is the value of the resistor and the capacitor of the "funky bridge"?
7.) What is the value of the "extra resistor"?

I really tried hard to read the color-coded resistor values from the photos I found on the Internet, but it's impossible to tell them 100%. Any contribution is highly appreciated! C'mon you Rev 6.2 / Rev 6.3 owners, give me a helping hand

[amigasith]

Found the answers to 6.) and 7.) myself In the schematics from here: www.amigawiki.org/dnl/schematics/A2000_R6.pdf

So here they are:

6.) 68 Ohm and 270 pF
7.) It's the same value as the original R215: 1 Ohm

[cpiac64]

sorry for delay, i don't have time this week

[amigasith]

Originally Posted by cpiac64

sorry for delay, i don't have time this week

No worries mate Take your time - there is really no hurry for this project. Thanks for your willingness to have a look, I really appreciate it

[TheDarkCoder]

Hello,

I bring back this old thread to ask for more information. A friend recently brought an A2000.
The PCB says that it's a 6.0. However there is a sticker on it, with printed 6.2. Is it possible that it is a revision 6.2, or genuine 6.2 have "6.2" printed on the PCB?

[Jope]

It has probably been reworked.

[TheDarkCoder]

@Jope: so you say that genuine 6.2 have "6.2" printed on the PCB, right?
I should examine closely the mobo to see if the supposed changes form 6.0 to 6.2 have been done or not

[Jope]

Originally Posted by TheDarkCoder

@Jope: so you say that genuine 6.2 have "6.2" printed on the PCB, right?
I should examine closely the mobo to see if the supposed changes form 6.0 to 6.2 have been done or not

Yes. Usually it's not really worth fussing over that much.. If you run into problems, then it's worth doing the upgrades..

[TheDarkCoder]

yep, we don't intend to do the changes (it seems to work with all expansion boards we plan to put in it), but I am just curious to check if the board has been modified (guess by C= ?) for otherwise I don't understand what the sticker means.
PS. we bought the 2000 recently and the seller told as it was a 6.0, as effectively printed on the PCB