|Re: HP-42S Turbo|
Message #8 Posted by Mike Morrow on 17 Nov 2012, 4:40 p.m.,
in response to message #7 by Peter A. Gebhardt
To determine the ROM version of the HP-42S:
1. Turn calculator ON.
2. Press and hold ON, press LOG, then release both keys.
[Displays the first step/screen of the self-test sequence.]
3. Press BACKSPACE key.
[Displays a line of hexadecimal data in two parts separated
by a colon. A series of memory nybble contents is shown to
the right of the colon, while the hex address of the left-most
nybble is shown to the left of the colon.]
4. Press the decimal point "."
[This tells the debugger to begin execution at the memory address
shown to the left of the colon (from step 3 above). The result of
this is a display for a couple of seconds of the letter of the
ROM version on the left side of the display.
For the HP-17Bii, in step 2 press the fourth from left "^" key at
the top of the keyboard.
The only HP-42S ROM versions I've ever seen are A and C.
The only HP-17Bii ROM version I've ever seen is B.
On the HP-42S, the nybble at 40300 sets the execution speed. The debugger is used to alter that location. Default is 7, max is F, but other values may be chosen as well to select other execution speeds, though that wouldn't be too useful. I've never tried 0 at that location.
I don't know if location 40300 does the same thing for the HP-17Bii.
One could experiment by trying step 3 to 7 that Gene listed on the web page cited in the first posting in this thread.
But whatever you try, the first time an EXIT takes place the speed resets to the default.