27 Feb
2024
27 Feb
'24
1:28 p.m.
you are correct. Packard Bell. apologies. And the picture on page 8 is (or is close to)
the paper tape reader I remember. So many fun things to program (I programmed in octal
only).
conditional instructions were "skip if", so if the first microinstruction in the
word, applied to the
second, if the second, applied to the next word, that is, 2 micro instructions, the first
of which
might also be a conditional...
two relative jumps in one word allowed a jump to be twice as big.
I *think* I should have the microcode programming book for this on paper. all boxed up
when I got
married and never unboxed after the divorce. brown and black cover.
<pre>--Carey</pre>
On 02/27/2024 12:40 PM CST Chuck Guzis via cctalk
<cctalk(a)classiccmp.org> wrote:
On 2/27/24 10:10, ben via cctalk wrote:
Is the "PB" Pitney-Bowes or Packard-Bell? I note that only because that
Raytheon bought out Packard-Bell's computer operation and re-dubbed
their models. So a Packard-Bell PB 250 became the Raytheon PB 250.
As regards the 440, it's on my short list of interesting "hybrid"
computers of the 1960s, which was a hot topic then: It was part of the
TRICE setup:
http://www.bitsavers.org/pdf/raytheon/trice/TRICE_440_Oct64.pdf
--Chuck
> On 2024-02-27 9:20 a.m., CAREY SCHUG via cctalk
wrote:
>> It's not a cassette, but the PB-440 (Pitney-Bowes), renamed Raytheon
>> 440 and its upgrade the raytheon 520 had a large reel paper tape with
>> a bidirectional read and an "operating system" Load the os, say we
>> want to run fortran, spin down to fortran, read the program in on 80
>> column cards (probably 2 pass, I don'trecall), automatically reload
>> the monitor when done, read and execute the program from cards.
>> Frequently used programs could be on the OS paper tape reel.
>>
>> btw, that computer was user level microcode. multiple "machine"
>> definitions, with typical 24 bit word, one instruction set optimized
>> for fortran execution, one for fortran compilation, etc (don't
>> remember exactly, as I only programmed in the microcode of mostly 2
>> micro instructions per word).