jmorriso@ee.ubc.ca (John Paul Morrison) (11/21/90)
The library posted by HP was pretty cute, but no one has yet mentioned an obvious use for it, once someone disassembles it: The library posted hooks into the error handling. This provides a very nifty way of implementing an error handler, without an RPL program ever knowing that errors even ocurred. The built in IFERR structure is too complicated: you wouldn't want to put IFERRs around every single operation.
akcs.joehorn@hpcvbbs.UUCP (Joseph K. Horn) (11/22/90)
John Paul Morrison writes: > The library posted by HP was pretty cute, but no one has yet > mentioned an obvious use for it, once someone disassembles it: > > The library posted hooks into the error handling. This provides > a very nifty way of implementing an error handler, without an > RPL program ever knowing that errors even ocurred. > > The built in IFERR structure is too complicated: you wouldn't > want to put IFERRs around every single operation. John, I doubt it. Notice that HYDE does not only change error messages, but ALL messages! (Example: press I/O SETUP and look at that bizarre I/O setup menu!) "Strange Case 998" is not a error handler, but a message translator. A "nifty" and practical use for this ability is the reason it's supported: foreign translation libraries that turn the HP 48 into a French calculator, or any language you please. Of course, foreign versions of ROM cards are just as easily implemented. Notice that the 48 manuals do not mention all the messages; for example, message #7 is normally "Warning:" but HYDE translates it to "Hey you:". -- Joseph K. Horn -- (714) 858-0920 -- Peripheral Vision, Ltd.
bson@rice-chex.ai.mit.edu (Jan Brittenson) (11/23/90)
In article <274ae35f:1200.1comp.sys.handhelds;1@hpcvbbs.UUCP> akcs.joehorn@hpcvbbs.UUCP (Joseph K. Horn) writes: > Notice that HYDE does not only change error messages, but ALL > messages! ... "Strange Case 998" is not a error handler, but a message > translator. A "nifty" and practical use for this ability is the > reason it's supported: foreign translation libraries that turn the HP > into a French calculator, or any language you please. c1d4 c110 Hmm... Let me guess. The font/message ROM is mapped in, the vector at #700f1 points to the message table base, the message is copied to RAM, the message/font ROM mapped out, and the message returned as a string object. Setting the vector to #Fxxxx will move the base to RAM xxxx? At least this is what seems to be the case after quickly glimpsing (after the HYDE stuff was posted) at the ML routines at #c1d4 (get ROM version) and #c110 (get message text). (Actually, I couldn't get HYDE to work on my calculator, so this is based on descriptions that have passed over the net. I screwed up, and didn't think it was important enough to bother with.) But it's Thanksgiving, and I've had a couple of glasses of wine, and may be a little tilted, so apologies to everyone if I'm driveling. :-) Disclaimer, blah, blah, etc.
akcs.matty@hpcvbbs.UUCP (James Matthew Huyck) (01/03/91)
Where can I find a copy of HYDE? I can't seem to find it anywhere! Please respond my posting a message here. ASC-> will work, I presume. Waiting hopefully........ Matt Huyck .
akcs.falco@hpcvbbs.UUCP (Andrey Dolgachev) (01/03/91)
For everybody who hasn't found it yet, the HYDE library, by Bill Wickes,
is found in message #1142 (Nov 15, HP48 Finishing School Dropout).
Enjoy,
---Falco