DF32x4 questions; software needed

From: Ethan Dicks <erd_6502_at_yahoo.com>
Date: Fri Apr 4 13:16:00 2003

--- "Dr. Charles E. Morris" <c.morris_at_townsqr.com> wrote:
> My "DF32x4" disk emulator is alive and talking to my 8/L and appears to
> be reading and writing blocks of data correctly.

Public congratulations!

---
> My "DF32x4" disk emulator is alive and talking to my 8/L and appears to
> be
> reading and writing blocks of data correctly. There are a few
> instructions
> that I did not implement (e.g. the "Maintenance" IOT's 6631-4 which the
> manual says are only used in "diagnostic programming".  - it
> would
> have taken quite a bit more logic to implement and there was no more room
> on
> the PC board; additionally the DEAL instruction would be used anyway,
> which
> combines the clear action with a load of these registers from the AC - so
> the clear would be superfluous. The DEAL and DEAC load/read register
> commands are, of course, implemented).
> 
---
> There are a few instructions that I did not implement...
> ... the DCEA instruction does not clear the extended address and EA
> registers... Ethan Dicks has pointed out that I should look at the
> drivers in OS8 and TSS8 to see if this will be a compatibility problem.
Sorry I didn't get back you earlier, but over on David Gesswein's
searchable software archive...
RTS/8 DF-32 driver (probably will never matter, but good background info)
http://www.pdp8.net/pdp8cgi/os8_html/RF08.PA?act=file;fn=images/misc_dectapes/DEC-S8-ORTSA-C-UC2.tu56;blk=290,10,0;to=auto
A code snippet from 
http://www.pdp8.net/pdp8cgi/os8_html/DX.12?act=file;fn=linctape-images/os8l/ds8-2nd-tape.linc;blk=184,80,0;to=auto
/ THE ROUTINE LINCDO CLEARS DF32 FLAGS TO ALLOW
/ A LINC DATA BREAK.  IF A DIFFERENT DATA BREAK
/ DEVICE IS IN USE THE APPROPRIATE MODIFICATIONS
/ SHOULD BE MADE.  (NOTE BY CLEARY)
LINCDO,	0		/EXECUTE A LINC PROGRAM
	DCMA		/CLEAR ANY DATA BREAK FLAGS
	DCEA		/THESE ARE FOR DF32
	TAD (LINPRO)
	ISSP		/SET UP LINC PC
	CLA
	TAD (10)
	ICON		/SELECT LINC
	TAD (2)
	ICON		/START LINC
	NOP
	TAD (-1)
	ICON		/DESELECT LINC
	CLA
	JMP I LINCDO
... shows the use of DMCA and DCEA to clear a disk, rather than DEAL.
Not exactly what you were looking for, but perhaps someone else has the
sources at their fingertips (I'm behind a restrictive firewall at the
moment, so my searching is somewhat limited).
As I mentioned earlier, I've only done some basic DF32 twiddling
from a PDP-8/i to prove that the interface mostly worked (and to
diagnose my repairs of a smoked rotation sensor board).  I've never
had the joy of an 8K machine + DF32s, so I've never had an OS to
explore them.
-ethan

Received on Fri Apr 04 2003 - 13:16:00 BST