lishka@uwslh.slh.wisc.edu (a.k.a. Chri) (08/18/90)
kaufman@delta.eecs.nwu.edu (Michael L. Kaufman) writes: >2) The deal with older ROMS is, you call HP and get on the list. Then around >the end of the year they send you a letter telling you where to send your >48sx. Then you send it in and get back a version E rom. The catch is that >they are only doing this for revision A, B and C. The good part is that it >is free. And now for the obvious question: where in HP does one call? Tech support or something? I have a revision A ROM that has worked fine for me, but I would truly like to have the clock in the status area (I keep it off now because I am doing too many transfers for software development). Does anyone at HP want to comment on this (Mr. Wickes)? Or at least acknowledge that something like this will happen, so we aren't left in the dark? If this upgrade is free, I will be impressed. Complete hardware upgrades can be expensive. One final thought: in the future, HP may want to design their calculators so that it is fairly easy for a calculator *owner* to upgrade their machine. HP calculators have passed the point where they have simple software built in. Future calculators should also be expected to have bugs in the early software revisions. Therefore, an upgrade path should be designed into the machine. HP should at least make the ROM chip easy to replace, and then figure on sending a "bug-free" ROM to all owners of early machines. The best way to learn is from past mistakes. -- Christopher Lishka 608-262-4485 "Dad, don't give in to mob mentality!" Wisconsin State Lab. of Hygiene -- Bart Simpson lishka@uwslh.slh.wisc.edu "I'm not, Son. I'm jumping on the bandwagon." uunet!uwvax!uwslh!lishka -- Homer Simpson
madler@piglet.caltech.edu (Mark Adler) (08/20/90)
Christopher Lishka writes: >> HP should at least make the ROM chip easy to replace, and then figure on >> sending a "bug-free" ROM to all owners of early machines. This may not be the best way, considering the size of a calculator and HP's very tight packaging. I think a better and more versatile way is to have some ROM vectors in RAM that can be patched and replaced with code in RAM to allow field upgrades of the ROM code. I'm sure there is already a dispatch table (or tables) in the ROM somewhere that could simply be copied to RAM on a total reset. On the next HP calculator, I'd expect the impact on RAM space to be small and well worth the investment. HP dealers could simply get the mods on a ROM card and download them into customers' calculators from a store calculator. They could also be distrubuted by HP on floppy disks for IBM's, Macs, and whatever they choose to support. This mechanism could be used to provide speedups to certain potions of the code by converting from RPL to machine code. And the possibilities for hackers are endless ... Mark Adler madler@piglet.caltech.edu