[comp.sys.misc] Info on DG-1 Laptop wanted

jimv@hienergy.East.Sun.COM (Jim Vienneau - Sun Microsystems) (04/24/91)

I have aquired a DG-1 laptop (yes DG made a laptop). It seems to work pretty
well, but I'd love to hear from anyone with a technical knowledge of it's
internals. I was hoping to use it for a portable TCP/IP host but I can't seem 
to get any comm software to talk to the serial port. It's internal terminal
program seems to work just fine though. Any advise would be appreciated!


Jim Vienneau, Sun Microsystems Inc - Billerica, MA
Email: jvienneau@east.sun.com   Amateur Radio: WB1B
Good old Ma Bell (well old anyway): (508)671-0372

shuford@cs.utk.edu (Richard Shuford) (04/24/91)

jimv@hienergy.east.sun.com says: 
>  "I have acquired a DG/1 laptop....but I can't seem to get
>  any comm software to talk to the serial port."

You'll probably want to hunt down the November 1984 issue of BYTE magazine
and read the cover story (a "product description", not a review):

    "The Data General One" by Gregg Williams and Ken Sheldon.
    BYTE, November 1984, Vol. 9, num. 12, pp. 102-109.

It has been a while since I examined a DG/1, but if I recall correctly,
DG's quest for low-power operation with 1984 technology (uh, chips made
that year, not Big Brother viewscreens) led the designers at Nippon Data
General to use a serial UART chip different from the 8520- or 14650-type
devices usually employed in MS-DOS machines.  Ergo, software that expects
to directly drive the 8520 chip can't find it.

All is not lost, however.  The DG/1's BIOS knows how to talk to whatever
UART it has, though, so if your communication software used BIOS calls
then it might possibly work.  I believe also that a special version of
MS-DOS Kermit for the DG/1 is available from Columbia University (FTP from
the host watsun.cc.columbia.edu).

Since source code for the driver that MS-Kermit uses is available, you
could with some amount of labor incorporate it into a SLIP driver for your
TCP/IP.  (Better yet, forget SLIP and write a PPP, point-to-point-protocol,
driver for it.)  If you are good at macro-assembler....

The DG/1 is not the only machine that was made with a non-8520 UART:
others were the Seequa Chameleon and the DEC Rainbow 100.  (The UARTs in
both those machines are arguably better than the 8520.)  Then the industry
decided that register-level hardware compatibility with the IBM PC was the
way to go, and those machines faded from importance.
-- 
....Richard S. Shuford  | "Do not rebuke a mocker or he will hate you; rebuke
....shuford@cs.utk.edu  |  a wise man and he will love you.  Instruct a wise
....BIX: richard        |  man and he will be wiser still."  Proverbs 9:7 NIV

kurt@photon.tamu.EDU (Kurt Freiberger) (04/24/91)

OK, what DG laptop is it????  Is it a Model 2, Model 2T or Model 1????
I'm moderately intimate with it.  If you can describe it, I can get the info 
to you.  
  Let's see.  The model 1 uses a big green battery pack.  The model 2 has an
internal battery pack (LCD display), or external power supply (EL display)
and the 2T uses flat battery packs that are replaceable by removing a lid
in front of the display.
  The model 1 uses a CMOS 8251.  The CMOS 8250s weren't out yet.  I
can send you a copy of Crosstalk that will work with it.  There is a port of
the ka9q TCP suite that is workable.  The model 2/2T has an 8250.  The trick is
that you have to turn the power on.  Do you have the MS-DOS that comes with
it?  The mode command does it.
Cheers, Kurt

My email posting bounced, so could you send me email to continue this?
Thanks.
-- 
Kurt Freiberger, wb5bbw	  kurt@cs.tamu.edu   409/847-8706
Dept. of Computer Science, Texas A&M University
*** Not an official document of Texas A&M University ***

peter@ficc.ferranti.com (Peter da Silva) (04/25/91)

In article <1991Apr24.040234.18071@cs.utk.edu> shuford@cs.utk.edu (Richard Shuford) writes:
> General to use a serial UART chip different from the 8520- or 14650-type
> devices usually employed in MS-DOS machines.  Ergo, software that expects
> to directly drive the 8520 chip can't find it.

In fact the chip used was a standard part in the process control industry,
and when I found out that the IBM used a different part (the DG-1 was the
first PC-compatible I'd ever used) I was blown away. Again IBM chose a
technically inferior part for no good reason I could see!
-- 
Peter da Silva.  `-_-'  peter@ferranti.com
+1 713 274 5180.  'U`  "Have you hugged your wolf today?"

carlson@mrx.webo.dg.com (James Carlson) (04/30/91)

8520?  I think you mean 8250.
Yes, the old DG-One and some of the follow-ons used 8251s rather than 8250s.
You can probably look these up in some Intel books.
No, I don't really know why they did that.
-- 
Disclaimer:  My company neither knows nor cares what I say.
.//.