7 Aug
2011
7 Aug
'11
4:57 p.m.
replying to ard at p850ug1.demon.co.uk (Tony Duell)
> Nice! There's been a resurgence in
appreciation of the "classics".
The 5160 I just mentioned with 4 floppy drive
How did you accomplish that?
- a controller that honors all 4 drive selects, not just 2
- primary & secondary disk controller
- Compaticard or other disk controller
at "non-standard" address & IRQ?
My pre-PC systems (mostly Z80 CP/M)
all support 4 floppies per the original specs.
But NOOOOOOOOOOOOOO, the PC's "cable twist" ruined that,
limiting things to 2 floppies and 2 hard drives per controller.
Not 'till SATA have we been able to un-do that mistake :-(
2 hard drives
Awww, come on, you can do better than that :-)
I have a 80386 DOS system running MFM, ATAPI/IDE and SCSI.
The "4drives" shareware was the first DOS support I found
for the hard drive controller at alternate addresses & IRQ.
MDA and CGA cards,
Dual display? What programs support that?
4 serial ports, 24 line user I/O (8255-based), etc.
Not all original IBM of course
Ah yes, that reminds me of the excitement of reading
Computer Shopper and all the computer shows,
always with new upgrades: higher res graphics, more memory, etc.
Every month or so, ALL the vendors had a different brand
of add-on card. For a while it was a box with a king playing card
on the cover. Then Pine Technologies. Then something else.
For those of us USING the stuff at the time,
we were always upgrading it piece by piece.
That's why it's so hard to find one with all original parts.
A PDP8/e with 32K words of real core
Do the boards have clear plastic for you to see the cores?
That's such a treat: true non-volatile memory!
> My high school started everyone with programming
BASIC
> on the HP 9820A:
I find that hard to believe for one good reason.
The HP9820 never ran BASIC...
You got me there.
It was kinda almost similar to BASIC.
It's so close that I totally forgot
when I converted to BASIC.
Since BASIC has so many "dialects",
I guess that fuzzed my memory a little.
Thanks for the clarification.
The HP9820 was HP's first infix-notation
(as opposed to RPN/postfix) calculator
and used a language that developed into the 'HPL' of the 9825 etc.
It was such a pleasure using an instant response interactive machine!
No waiting for carriage-return for the interpreter to handle the line
or waiting for the compiler for an all-or-nothing result.
You may have guessed I have something of a soft spot
for these machines.
As an undergrad, I never had the budget for a HP calculator
nor access to a HP desktop like my high school's.
Somehow a TI-55 sufficed for me as an EE undergrad.
Looking back, I just can't see how. It's *SO LAME*.
I got a HP-28C when it was new and it's still my primary calculator.
I really need that 4 line display to use RPN so I can see the stack.
-- jeffj