27 Feb
2024
27 Feb
'24
6:34 p.m.
I'd say the real cost is the second or third system to get spare parts.
that is why I want to replace the WD chip. the microprocessor talks to it
at bus speed. the os knows it has to wait, though some waits are for the
wd chip to say it is done. a SIMPLE mod to the legacy OS can eliminate
those waits, thus IO as fast as a real hard disk, maybe as fast as an SSD.
I love the 1130, the only I/O instructions given to the printer are input.
And the 1620 does addition and multiplication by table lookup.
Again, even if somebody offered me a complete IBM model 30 with disk and
tape drives, I could not afford the shipping. would probably have to
take out the a window to get it inside (big expense), and it might
instantly become a basement installation. I'd have to have much more
power and A/C installed. And no spare parts. Now, any front panels...
Even recreations of front panels would be treasured. In the 1980s the
Bradford exchange had a 360/40 front panel mounted in their space with
lights artificially flashing. I might even attempt to modify an
emulator program to flash the lights appropriately.
<pre>--Carey</pre>
On 02/27/2024 7:16 PM CST ben via cctalk
<cctalk(a)classiccmp.org> wrote:
On 2024-02-27 3:09 p.m., Paul Koning via cctalk wrote:
Dumpster diving is a 0 dollar budget.
People could afford the APPLE II, 8080 S-100 bus, SWTPC 6909. I assume
with careful shopping one can rebuild them for about the same price, in
small quanities.
Power supplies require harder to find parts.
Main frame rebuilding is costly, but I suspect the real cost is I/O
that can't be duplicated. A hardware emulation using microcode to me
is real computer, a windows fly by night emulation is not, as the base
platform is too unstable.
On Feb 27, 2024, at 4:49 PM, CAREY SCHUG via
cctalk <cctalk(a)classiccmp.org> wrote:
Religion warning: I was a mainframer. Since at any practical budget, they can only be
emulated,
Depends on your definition of emulated. Is an
FPGA version merely an "emulation"? You might say yes if it's a functional
model. Arguably no, if it's a gate level model.
I have bad luck with FPGA's, too many timing issues with routing.
I have better luck with a 2901 4 bit alu and some support logic mounted
on a small pcb.
Suppose you had schematics of, say, a KA-10. You
could turn those gates into VHDL or Verilog, and that should deliver an exact replica of
the original machine, bug for bug compatible. That assumes the timing quirks are
manageable, which for most machines should be true. (It isn't for a CDC 6600.)
paul
The IBM 1130 is also a pretty scary machine inside.
The blog is here.
https://rescue1130.blogspot.com/
Ben.