At 2:47 AM -0700 5/29/10, Eric Smith wrote:
Found it. The "UI+" command will slow down a
1540 for use on a C64,
and "UI-" will speed it up again. Apparently when they wrote the
1540 firmware they anticipated that the bus might have to be slowed
down for use with some future computer.
Although the 1541 defaults to slow mode, the same commands work, so
when using a 1541 on a VIC-20 you might want to give the "UI-"
command.
Example: OPEN 15,8,15,"UI-":CLOSE 15
Eric
Eric,
Am I reading correctly that the 1540 sends data faster than the 1541?
This brings up the obvious question, can you 'downgrade' a 1541 to a
1540! :-) I have multiple working 1541's, but only have 1 or 2
1540's in questionable condition (I believe one is literally in
pieces).
I'm still trying to organize and sort out the stuff I got in the two
loads, and have barely looked at the hardware itself. I dug through
a couple boxes of software, doc's and magazines last night. Some
very interesting stuff.
Zane
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh at
aracnet.com | OpenVMS Enthusiast |
| | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| PDP-10 Emulation and Zane's Computer Museum. |
|
http://www.aracnet.com/~healyzh/ |