2 Dec
2004
2 Dec
'04
8:28 a.m.
At 01:32 PM 12/2/2004 -0500, you wrote:
Hi Ashley,
Good enough.
FWIW, Guy's program decodes to the following:
001000 005000 CLR R0
001002 005200 1: INC R0
001004 006100 ROL R0
001006 000005 RESET
001010 000775 JMP 1B
The instruction of interest is the RESET, which sends an INIT to
the UNIBUS for 10ms. It must also have the effect of displaying
the contents of R0 in the DATA display, or perhaps whatever register
was last referenced. I figured that there was an instruction which
would behave in this manor, but did not recall what it was...
--tom
Tom Uban
wrote:
Ashley,
Did you get a response on your question? One point
to keep in mind is that the various processor types
behave slightly differently. The typical method used
to do the "Cylon" lamp effect was to use the console
switch/display register (777570). A pseudo code program
would be something like this (translation left as an
exercise for you:-):
Write '1' to console display register.
Lamp Loop:
Load spin count into register 2.
Spin Loop:
Decrement register 2.
Branch if non-zero to Spin Loop.
Rotate the console display register value left.
Branch to Lamp Loop.
This code will continually rotate one lamp from right to
left across the display. A more complex version would switch
directions when the lamp hits either end.
Now for the problem. Only some processors (45, 70, perhaps
others, but I don't think the 35 or 40) support display of
the console switch/display register.
There may be some other more generic method that works on
all processors, but I'm not sure what it might be...
Hi Tom,
I got a little "single rotating bit" program, coutesy of Guy Sotomayor,
who's been a *BIG* help to me. I used this little program to do some
basic testing on my PDP-11/40. It continually rotates one lamp across
the display. This program was loaded as follows:
Load address 001000
Deposit 005000
Deposit 005200
Deposit 006100
Deposit 000005
Deposit 000775
Load address 001000 and press Start.
You should see a bit rotate around on the data LEDs.
If anyone has any more interesting programs that can be toggled in
for "blinking light" effects, I'd be interested in trying them out.
After toggling in a couple of these types of things with the front
panel last night, I decided to move on to bigger things. I hooked up
an RL02 and was able to successfully boot RT11 v5.3, XXDP 2.5,
and my Wofford Witch RSTS/E v7 system.
Life is good!!!
Ashley