A3000 - how to switch off CPU Slot

[AmireX]

Hello, I'am a happy owner of two A3000's. One running Amix and the other one running AOS 3.9. Now I've got an order of my wife to reduce the waste of space and to use only one of these machines (an good idea at all :-)). But now my problem: I have the Amix harddisk built in the AOS 3.9 machine, so that I can select from where to boot via bootmenu. But in the AOS 3.9 machine a Cyberstorm 060 accelerator is running and so Amix is not working on this machine. Now I'm looking for a little hardware modification (motherboard or Cyberstorm) so that I can switch off the Cyberstorm via external switch before booting Amix. Is there a possibility to cut special bus request signals from the CPU slot like /CBR or /BOSS ?? I tried to cut the power for the CPU slot, but there are too many lines :-? Hope anybody can help (so my wife is happy again and I'm too  :-D

[Framiga]

Which Cyberstorm model?

Try to press the "a" key during the boot.

[AmireX]

Cyberstorm Mk II 060 50 MHz. The "a" key seems not to work :-( Is there a Cyberstorm card which could turned off via keyboard during startup ??

[KThunder]

hey
 
any hardware hack that big would make me seriously nervous, the possibility of burning your card or miggy or both is too great.
so whats my solution? sell me the card then you wont have to worry about disabling it.  :-D  kidding
i got an order from my wife a few years ago so i got rid of my two mint a1000s and bought an a1200
ive been aquiring parts for something more allong the lines of a big box since then.
good luck

[Framiga]

Cyberstorm MKIII and CyberstormPPC as well even if, to be honest, i've never tryed it (A4000 here).

By the RomUpdate doc:

o Key "2" disables the processor on an 1200 ONLY.
  o Key "s" pressed during booting disables the SCSI,
            cdrive, bootmenu, bootmenu settings.
  o Key "c" pressed during booting disables 31khz bootmonitor
            and cvppc support
  o Key "m" pressed during booting disables the memory
  o Key "p" pressed during booting disables the pci
  o Key "a" pressed during booting disables all

[AmireX]

I'm very nervous too :-). But I have 2 backup motherboards, but no backup cyberstorm .. So better the motherboard burns then the cyberstorm ..

But seriously .. Amix with 030 and AOS 3.9 with 060 on the same machine would be great for me. This makes a lot of things easier, for example the data exchange between the OS's via A3070 tape drive (Now I plug the drive from one into the other).

On the other hand, a man needs a problem  :-D

[AmireX]

So I have the wrong cyberstorm version :-( A very nice solution without soldering iron :-)

[Framiga]

I'm sure, that there is someone here who could help you about the hardware route.

The MK2 works with the clock source in INT mode (as the built-in 030)

mhh . . .don't know . . . if it would enough to cutOFF the CS power, still the problem with all the signal addresses lines . . . don't know

[AmireX]

The CS power ? Is this a signal name on the CPU slot ?

[Framiga]

no, no CS as CyberStorm power lines.

but . . ."don't try this at home" :-)

[alexh]

Surely the best method would be a software method? Always boot to OS3.9... run a little program that switches off the Cyberstorm and reboots to Amix?

[AmireX]

Do you know such a program ? Never heard about this way ..

In the book "AMIGA intern" the communication between zorro cards or CPU Slot and the mainboard cpu is described as follows.

First the coprocessor sends a /CBR (not /BR like other custom chips) to request the bus. Via buster chip this signal goes to the mainboard processor and this one answer with /BG. This /BG goes via buster to the coprocessor as /CBG and this one gives back the /BOSS signal (not /BGACK). Now the bus is fully controlled by the new processor. All the other DMA cards and chips can access the bus via /BR -> /BG -> /BGACK and work like ever.

So my idea to cut the /CBR signal. This signal goes to a special PAL chip (U701) on pin 19. I have made the cut there but without success :-( Another signal /CBREQ is sended direct from cpu slot to the buster. But I havent found any description ..

Last not least my Amiga still works and is stronger then ever after this little operations :-)

[AmireX]

Today I bought a Cyberstorm MkIII from Effy and I'll tell wether I can switch off it and then rebooting to Amix.

So I can put away my soldering iron :-)