10 Nov
2010
10 Nov
'10
1:53 p.m.
On 11/09/10 10:44, Roger Holmes<roger.holmes at microspot.co.uk> wrote:
That is definitely true here. :-)
> From:
Johnny Billquist<bqt at softjar.se>
>
> Gah. I have no idea what PPU mean, nor PP.
You're probably just not old
enough. In the 50s the main processor was called the CPU
(Central Processing Unit) to differentiate it from the various PPUs, (Peripheral
Processing Units). The first machine I programmed, the IBM 7094 had a CPU and two PPUs,
one to read cards and write the images to tape transports, which would then be switched
over to the CPU to read, compile and execute the job and write the results back to another
tape transport which then got switched to the other PPU which then transferred the tape
image to a line printer.
Thanks. That explains it.
Somehow now (when most peripherals have embedded
processors which could be called PPUs) we seem to have stopped using the term.
Yeah. It might have gotten lost in the inbetween years when computers
were trying to get rid of, at the time, expensive peripherials (they
were expensive enough without being their own computer).
I only started playing with computers in those inbetween years. :-)
Johnny