New PPC design

[Brass]

How about something a bit larger than a mod, I have schematics for a PPC based PC using the IBM PPC 970 wana have a go at making a new Amiga in conjuction with the Xilinx based amiga project

[Zetr0]

@Brass

Sounds really COOL, but thats a lot of low-level software engineering.... it would be interesting

[Merlin]

@ Brass

An Amiga without a Motorola 68xxx isn't an Amiga in my eyes... even Minimig uses a 68000 IIRC.

A PPC based machine is, as you say, a PC (or maybe a Mac).

Merlin

[Charlie]

Originally Posted by FOL

...and you wouldnt believe what i cut it with. A pair of scissor's .

Ah! My kind of modding.

Good show old chap!

@Brass:
Despite being a 68k-boy, sounds cool to me.
Question: Such a project is WAY beyond me & I suspect would even stretch the recognised hardware guru's on this board...
...how about you??

[Brass]

Originally Posted by Zetr0

@Brass

Sounds really COOL, but thats a lot of low-level software engineering.... it would be interesting

I had a couple of thoughts actually one of which was to put the 68K in control and emulate the signals that would cause the CPU to be disabled in hardware after the OS had loaded thus creating in effect an 68k in control initially and then letting the PPC have control. Me thinking OS4 for classics

The other thing I was thinking about was the possibility of replacing the existing PPC on my phase 5 board with a Golden Eye 300Mhz version to just up its speed ... or... and I don't know if this is doable but I have seen it done on PC's replace the 603e with a later CPU.

My thoughts on this are to have the existing CPU removed a PGA socket put it its place then either through a PGA socket that had internal routing or via a circuit board that plugs into the origional PGA so that a new voltage regulator could be added and/or circuit lines could be rerouted if required, this PGA or circuit could be plugged into the PGA on the board and the new CPU plugged into it.

If there is a firmware problem for identification in this case then I would suggest that the origional CPU also be added and told to shut up in much the same way that the 68k does on your amiga 600 accelerator but after the firmware has gone "yes thats the cpu I want"

I know this is a lot to digest so ill wait to hear back.

[Zetr0]

@Brass

indeed interesting, there are some problems and there as some existing project that are similar in the obsticles that they face...

when i get a bit more time i will show you whats going on in this area..

[Brass]

Originally Posted by Zetr0

@Brass
when i get a bit more time i will show you whats going on in this area..

Cool I look forward to hearing about it all.

It could be a fresh set of eyes and perspective may help

BTW I have found out that the MPC 745 & 750 series ( 750 is from memory it may have been 755 ) are software and pin compatible with the 603e, this means in theory provided you have the right timing it would be possible to just drop in replace the cpu.

[Brass]

Ive decided that Im bored with waiting for something to happen on the Amiga scene.. So Im starting into this project with another smaller project just to see if I can do it.
My plan is to:

Make an AT card which has only a 68k a LED and maybe a small amount of memory.

Send this AT card a program or an instruction at a time to turn on the LED

Connect the 68k socket on my B2K to the at card on the PC via the socket that did have the 68k and emulate the CPU via software on X86 with resultant signals being manipulated on the 68k socket.

I may not acheive anything but itll give me something to do while I wait to see what happens and may help towards a PPC board.

[Zetr0]

hmmm i like it but i also like the idea of an x86 chip as apposed to a ppc!

[alexh]

Originally Posted by Brass

BTW I have found out that the MPC 745 & 750 series ( 750 is from memory it may have been 755 ) are software and pin compatible with the 603e, this means in theory provided you have the right timing it would be possible to just drop in replace the cpu.

It will cost you over £100 to have the old PPC chip desoldered and the new one soldered on and x-rayed to make sure it's in the right place.

Unless you have access to a BGA rework station and an x-ray/optical scope?