reynolds@fsg.UUCP (Brian Reynolds) (06/18/90)
I seemed to have crashed my new HP-48SX. All the pixels in
the display area are on except a column near the left edge and three
columns near the center. The busy annunciator is also on. The
calculator doesn't respond to ON-minus, ON-+, ON-C, ON-D, ON-AF or
OFF. It also doesn't seem to do an auto-poweroff. Does anyone know
how to get it out of this locked state? Is there a way to do a
cold-reboot, or hardware reset? The store I bought this from has a
ten day return policy. If I can't unlock it, I'm going to try and
exchange it tomorrow (Monday). A detailed (read long) description
of what I think brought about this state follows. If you're not
interested in the gory details hit 'n' now.
A couple of days ago I keyed in the PEEK and POKE routines
from the "Introduction to HP 48SX Internals" that were posted a
while ago. BYTES reported the correct size and checksum. I then
set up the alternative to SVC (a subdirectory of { HOME } with the
HOME key reassigned) that was posted a couple of days ago. I
downloaded USAG (from the serial disk) and keyed in WALK (from the
manual). These both passed BYTES. I decided to ORDER the { HOME }
directory to move my subdirectories to the front of the list, and
alphabetized the programs. (This may have been my first mistake.) I
had one subdirectory under my alternative HOME.
Today I decided to download the APPT program from the serial
disk. I switched to { HOME } and downloaded the APTDIR, but forgot
to set binary mode on my computer so it showed up as just a regular
variable. It didn't have the extra pixels in the menu that mark
directories and when I pressed the menu key I got some junk in stack
level 1. I PURGEd the APTDIR variable, set binary mode on my
computer, and did the download again. This time I couldn't find
APTDIR. I only had three directories so I looked through them all.
I couldn't find APTDIR anywhere, even though both my computer and
the HP said it got transferred. MEM said I had used about 13KB of
memory during the download. I decided that I might have screwed up
when I entered PEEK and POKE (which I hadn't actually used after
keying them in) so I did an ON-AF and answered YES to try and recover
memory. At this point the calculator went away. After about 5 or
10 minutes (with the calculator still in the busy state) I decided
something must have gone wrong. I couldn't halt or reset the
calculator. I then made my second (at least) mistake.
The manual warns that taking the batteries out with power on
could cause a memory loss. It also warns that keeping the batteries
out for more than 2 minutes can cause memory loss. I decided that
losing memory was better than being locked in this memory recovery.
I took the batteries out and left them out for about 5 minutes. Now
I'm locked up even worse and I have no idea how to get out. Any
ideas?
DISCLAIMER: In no way do I mean to imply that either of the above
mentioned postings caused or lead to my problem. I mentioned them
only to let someone more knowledgeable than I am know what state my
calculator was in before I screwed it up. I think it may be
possible that my reordering of the PEEK and POKE programs screwed up
some memory, but that was my own action.
Thanks in advance,
Brian
--
Brian Reynolds | reynolds@fsg.com
Fusion Systems Group | -or-
225 Broadway 35th floor | ...!uunet!fsg!reynolds
New York, NY 10007 | Phone: (212)285-8001