del@dataio.UUCP (07/30/84)
< nonononono ple-ease, please leave a line for me > - I need some help in configuring my HP-41. Sales people are of no help. The problem is I need more memory, which wouldn't be a problem except I am concerned with a compatibility problem. I have a 41C, which I installed a quad memory module in. The memory module is great, but since I am a student and an engineer, I have used it all and need more. (I have to delete programs to make way for temporary ones just before a test) I considered buying a card reader, but heard that the Extended-Functions-Memory-Module can be used to store programs. 1) Is this true? 2) If not, what other options are there besides the card reader? 3) The module literature states that the module contains 127 registers of memory that can be used like any other memory in the calculator. Is there a conflict with the quad memory pack? (The calculator manual states it is not a good idea to overlay memory) 4) Has anybody used the Extended-Functions module? What do you think? Mail answers to these questions to the address below. They will not be graded. Thank you in advance. Erik Lindberg AKA del ...!uw-beaver!teltone!dataio!del ( I used to call myself a hacker.... )
rjnoe@ihlts.UUCP (Roger Noe) (08/07/84)
The Extended Function/Memory module can indeed be used for storing programs.
Beyond this, you can add up to two Extended Memory modules (with the quad
memory module already in place this will fill up your four ports). I have
forgotten just how much memory this would give you, but it's quite a lot
for a handheld computer. Extended memory must be "swapped in" to main memory
(using Extended Functions) before programs contained there can be run.
Other options (besides the magnetic cards) include the digital cassette drive
which can store enormous amounts of data. I think this might require use
of the HP-IL loop, but I'm not sure about that. I have yet to fill up my
quad memory although I have at times used all four ports, what with the
Extended Functions/Memory module, the PPC ROM, and alternating between my
optical wand and application pacs.
There is no conflict between main memory (bascially what a HP-41CV starts with)
and Extended Memory. I have used the Extended Functions module and I like it.
The documentation leaves something to be desired, however.
--
"It's only by NOT taking the human race seriously that I retain what
fragments of my once considerable mental powers I still possess."
Roger Noe ihnp4!ihlts!rjnoesmd@cvl.UUCP (Stanley Dunn) (08/10/84)
The extended memory module does not overlay the quad memory in the 41. I prefer to think of the extended memory/extended functions module as " file space " for the 41 (you see, it includes an extended memory directory command - EMDIR). With the EM/EF module, I can save a program I am working on, freeing up the space in the main memory. I only use the card reader to archive stuff. The 127 registers are independent of the main 41 memory. In fact there is also another extended memory module to expand the 127 register EM space. The two of these combined should be more than enough space. Stan smd@cvl Univ. of Md. Computer Vision Lab
sechrest@orstcs.UUCP (sechrest) (08/10/84)
The Extended memory is treated like the cassette in the way that you access it. It is in a different part of memory than the "main" memory. The "overlaying memory" comes from somepeople modifying their systems to install their own memory. You must be carefull when you do that. The cassete drive MUST have the HPIL interface. You can upgrade to a 41CX which has most of the memory built in plus extended functions plus the timer. Having the card reader or the cassette is usefull because you can archive programs for other people and other places. John Sechrest orstcs!sechrest