Turbo SE accelerator

[lisa2]

I have a Mac SE with a Mac Memory Turbo SE accelerator.  This board has a 16Mhz 68000, a 68881 math coprocessor, and 4 Meg RAM.  It works very well, but I do not have any drivers or documentation for it.  Does anyone out there have more information (or the software) for this board?

Thanks,

Rick

 

[Trash80toHP_Mini]

Interesting, I was wondering where the CPU might be, hadn't seen a PLC(?) socketed 68000 before this. Is that a PDS passthru connector on the back edge?

More pics please!

 

[lisa2]

Yes, it does appear to have a PDS pass-thru connector on the back edge, but it is only labeled P1 so with out documentation I cant be sure what it is.

The board has 4 SIMM sockets on it each populated with 1 Meg SIMMS, the ROMs are pulled from the SE logic board and installed on the Turbo SE board.  There also is a small amount of RAM on the SE logic board, only 2 SIMMs, I am guessing they are 256K but I did not verify this.   There appears to be no hacks on the main board, everything is cleanly interfaced thru the PDS slot.

The finder reports the system as having 4Meg RAM, Speedometer reports the system as running about twice the speed of a stock SE, but Speedometer does not see the FPU.  Sound seems to work OK.  

Rick 

 

[Trash80toHP_Mini]

Sweet, sounds like the drivers must be in ROM on board if it's up and running at 16MHz. Not sure anything but detection at startup should be required for the 68000 to use the CoPro automagically? Prolly wrong on that. Run TattleTech to see if it detects the FPU and reports anything else interesting.

 

[gpbonneau]

I have exactly the same card in one of my SE, but without appropriate driver too  :-(

There are several jumpers on the card, with explanation on the back (I tried many configurations to test...)



It works very well, but It seems the copro is not used (may be a patch is necessary...)

In using Speedometer, the score of the CPU is better (x2) but only a small gap for the FPU.

The score is better with the ROM on the card which run to 16Mhz.

It is necessary to keep at least 2 RAM (256Ko) on the motherboard to work.



Anyway, the difference in using the Mac is visible.

Last thing, in my card the proc is a 68HC000 version (low power for laptop), I don't know why ?

 

[gpbonneau]

I found a test of this card in BYTE from March 1988.
https://archive.org/details/byte-magazine-1988-03/page/n157

This confirms that I need an INIT software to use the 68881. But no way to find it

If anyone has it ...

It also explains the use of the connector on the card, which was an option for a video card for an E-Machine Big Picture screen:

 

[CharlieFrown]

68HC000 cpu's are used in modern accelerators for Amiga, they are capable of running at 50 mhz(!). Would love to see HC based turbo for 512k/Plus.