English Amiga Board - View Single Post

bender · 18 January 2021, 06:17

Hello!

I hope someone can help. I have an Amiga 4000T with the following symptoms:

If I add a Picasso IV, it is not recognized at all. It does not appear on the early boot.

If I add a Deneb in Zorro 3 mode, it is seen in the early boot, but does not work. I cannot see the unit that it mounts (with Poseidon and other software to install) and I cannot see the "Deneb" animation that is normally shown at the start.

Both cards (Picasso IV and Deneb work perfectly as they are in a 4000D).

I have been visually inspecting the 4KT, checking continuity of the Z3 pins and nothing seems to be wrong, but then I realized that P701 (the "Arbiter" according the schematics on this site: https://www.amigawiki.org/doku.php?i...ice:schematics A4KT PDF Page 13), has clear signs of rework, maybe even being replaced. I can clearly see the solder is different and there are some solder blobs on the pins (no bridges though).

So my question is, could a bad P701 cause the issues I am seeing? And if it is defective, is it possible to get a replacement for that chip? Maybe a fix has was attempted to try and fix the issue with no success. It's been like this since i bought it years ago.

In the schematics P701 says "P16R4-15" and the chip in my machine says "TI16R4-15 58A8KKWF". Also, it says "PAL" in the schematics. I think those are programmable chips right?

I appreciate any help you can provide.

Thanks!
Efrén

18 January 2021, 06:17	#1
bender Registered User Join Date: Oct 2018 Location: Queretaro, Mexico Posts: 10	Amiga 4000T and Zorro 3 Boards Hello! I hope someone can help. I have an Amiga 4000T with the following symptoms: If I add a Picasso IV, it is not recognized at all. It does not appear on the early boot. If I add a Deneb in Zorro 3 mode, it is seen in the early boot, but does not work. I cannot see the unit that it mounts (with Poseidon and other software to install) and I cannot see the "Deneb" animation that is normally shown at the start. Both cards (Picasso IV and Deneb work perfectly as they are in a 4000D). I have been visually inspecting the 4KT, checking continuity of the Z3 pins and nothing seems to be wrong, but then I realized that P701 (the "Arbiter" according the schematics on this site: https://www.amigawiki.org/doku.php?i...ice:schematics A4KT PDF Page 13), has clear signs of rework, maybe even being replaced. I can clearly see the solder is different and there are some solder blobs on the pins (no bridges though). So my question is, could a bad P701 cause the issues I am seeing? And if it is defective, is it possible to get a replacement for that chip? Maybe a fix has was attempted to try and fix the issue with no success. It's been like this since i bought it years ago. In the schematics P701 says "P16R4-15" and the chip in my machine says "TI16R4-15 58A8KKWF". Also, it says "PAL" in the schematics. I think those are programmable chips right? I appreciate any help you can provide. Thanks! Efrén