11 Dec
2018
11 Dec
'18
8:34 a.m.
That's a beautiful old scope setup. I have a friend who collects this
stuff but he is very low budget and on the opposite side of the country
like me.
Marc
On Tue, Dec 11, 2018 at 6:15 AM Paul Koning via cctalk <
cctalk at classiccmp.org> wrote:
I made such a setup in college: we had an 11/20 with AA11 (and other lab
I/O gear). I hooked those up to the X/Y inputs of a scope, and a digital
I/O line to the Z input. Then loaded coordinate pairs into a buffer on the
RC11 disk, which was set up to do DMA directly to the AA11 data CSR.
Worked nicely, and with low overhead on a machine that certainly could not
afford to do refresh in software.
The classic example of a computer display like that is the CDC 6000
mainframe console. That is essentially a pair of oversized oscilloscopes
(with electrostatic deflection), with their X/Y inputs driven by a
dedicated display controller that includes a vector character generator.
paul
On Dec 11, 2018, at 7:59 AM, Toby Thain via
cctalk <
cctalk at classiccmp.org> wrote:
On 2018-12-11 1:17 AM, devin davison via cctalk wrote:
> The line about being used with an early computer as a display caught my
> eye. How would it be used as a display, what kind of graphics capability
> would it have? is there an interface for the thing for the pdp 11 or a
> modcomp? Those are the old systems i have on hand that i might be able
to
interface
to it.
A scope is at heart an electrostatic CRT with X and Y deflection (and
perhaps Z axis blanking control). Many older systems did have such
displays -- the PDP-1 is a well known example (e.g. see Marc and Lyle's
CHM demo on YT[1]). Imlac PDS-1 is another. And before _digital_
systems, scopes or X-Y displays were a typical output medium for
_analog_ computers.
For digital computers, output is point plotting, vector drawing, and/or
character generation depending on the sophistication (= cost) of the
hardware involved. You'd also need to find or write suitable software :)
Yes, there were interface cards for PDP-11, such as AA11 (dual DACs).