[net.micro] GODBOUT/COMPUPRO questions...

LIN@Mit-Mc@sri-unix (11/20/82)

From: Herb Lin <LIN@Mit-Mc>
I'm looking for certain information on GODBOUT/COMPUPRO systems...

(1) is there error-correcting circuitry available? (or parity checking?)

(2) they market an 8086/8087 board, but they claim that the 8086 is restricted to running at 5 MHz "with the 8087", vs. a 10 MHz speed without it. 

	(a) how come?

	(b) does this mean that the simple existence of the 8087
	inhibits 10 Mhz operation, regardless of whether the 8087 is actually
	in use, or can the 8086 run in 10 Mhz mode while the 8087 is either
	not in use or somewho disabled?  can it be disabled at all?

(3) can the 8087 be accessed while running 8 bit software?  For
example, if I had a fortran program wanting to do number
crunchingwhich was running on another card (e.g., their CPU Z card),
could I get at the 8087? Or is the 8087 a 16 bit job?

(4) how does the 8087 work anyway?  does the cpu see it as an I/O
device, or what?

(5) can anyone recommend a good hard disk (preferably with an
integrated tape back-up) which runs well with Godbout/Compupro
controllers?

(6) I've seen a few ads specifying particlar all-Godbout/Compupro
configurations, but for my needs, none of these are just what I need.
Does anyone do custom integration by mail?  if so, are they reliable,
etc...?

I will share all replies...

many thanks.

BILLW@Sri-Kl@sri-unix (11/20/82)

From: BILLW at Sri-Kl
The 8087 is a co-processor.  When the 8086 want to do floating point
operations, it uses the various ESC opcodes.  The 8087 reads this
from the bus, and by watching the status lines of the 8086, is able to
determine when tey are executed.  It then can read an operand from the
bus (which the 8086 fetches and discards durring the ESC operation).
I dont know wgether the 8087 can also control the bus itself, but I
assume it must (otherwise  it would take several ESC instructions
to load a full floating point number...)  All this means that there
is little chance of getting at the 8087 from another processor.

Presumably, the 8087 will only run at 5MHz because is is not as far
along the learning curve as the 8086.  The first 8086s were 5Mhz too.
Due to the above outlined tight coupling between the 86 and 87, they
must both run at the same clock speed.

BillW

UCBARPA.dag@Ucb-C70@sri-unix (11/21/82)

From: UCBARPA.dag at Ucb-C70 (David Allen Gewirtz)
Received: from UCBARPA.BERKELEY.ARPA by UCBVAX.BERKELEY.ARPA (3.227 [10/22/82])
	id A19732; 21-Nov-82 00:57:14-PST (Sun)
To: LIN at Mit-Mc, info-cpm at BRL, info-micro at BRL
Via:  Ucb-C70; 21 Nov 82 4:05-EST
Via:  Brl; 21 Nov 82 4:12-EST
Via:  Brl-Bmd; 21 Nov 82 4:27-EST
Via:  Brl; 21 Nov 82 2:48-PST

As far as I can tell, G & G Engineering is the best Godbout
integration house around.  They seem to know there stuff when
it comes to system integration.  Since they have Compupros
stamp of approval for integration work, it seems that they
may be what you want.  I spoke with them once and was
impressed by their knowledge.  (however, they have grown
considerably in the half year since then).  For your information
they are in San Leandro and San Francisco CA, in the 415 area.
I believe that their ads are in a number of the trade mags.  I
also believe they will do stuff by mail.  

Be forwarned however, they are not cheap.

Good Luck,
David