Using VIEW and AVIEW on the DM41X

Discussion around the SwissMicros DM41X calculator
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HPMike
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Location: DFW, Texas

Using VIEW and AVIEW on the DM41X

Post by HPMike »

Reference: HP-42S Owner's Manual, page 132

Using VIEW and AVIEW on the DM41X is the same as on the HP-41C, HP-42S and DM42. it will only work properly if flag 21 is set. There are two scenarios:

1) There is no printer plugged into the calculator, in which case flag 55 is clear. In this case, VIEW or AVIEW will pause halt execution to display the result, and resume execution when R/S is pressed.

2) A printer is plugged into the calculator, in which case flag 55 is set. In this case, VIEW or AVIEW will not pause halt execution to display the result, and will instead send the result to the printer.

If flag 21 is clear, then VIEW and AVIEW will ignore flag 55, and it will neither pause halt execution to display the result nor send it to the printer. This means that any program that uses VIEW or AVIEW must also set flag 21 at the beginning of the program. This is a bit confusing, because flag 21 being set means that printing is enabled (desired), such that if a physical printer is not present, you are virtually printing to the display.

If a calculator uses an IR printer, then it must be unplugged in order to see the results in the display during execution. On the HP-41C with an IR Printer module, this can be accomplished by XEQ PRTOFF and on the DM42 by XEQ PROFF. Since the DM41X lacks this command, the Thermal Printer module must be unplugged, to permit VIEW and AVIEW to pause and display results. Since PRTOFF and PROFF clear both flags 21 and 55, the program must set flag 21 again in order for VIEW and AVIEW to work properly.

Note that the original HP 82143A printer that physically plugs into the HP-41C calculator is detected (flag 55 set) even if it is powered off. So, the PRTOFF command is the same as physically unplugging the IR Printer module.
Last edited by HPMike on Mon Oct 26, 2020 10:51 pm, edited 1 time in total.
DM15L, S/N 00548. DM42, SN: 00159. DM41X, SN: 00973. DM32, SN 00054.
Thomas Okken
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Re: Using VIEW and AVIEW on the DM41X

Post by Thomas Okken »

I believe VIEW and AVIEW also halt program execution if the 82143A is connected but turned off. Note that flag 55 is set in this case.
Maybe the DM41X just needs a menu setting to emulate the "printer off" state?
Amphitryon

Re: Using VIEW and AVIEW on the DM41X

Post by Amphitryon »

HPMike wrote:
Mon Oct 26, 2020 6:34 pm
[...] 1) There is no printer plugged into the calculator, in which case flag 55 is clear. In this case, VIEW or AVIEW will pause to display the result, and resume execution when R/S is pressed.
  • Are you about to rewrite the manual? Then you should be precise, it makes a difference if VIEW and AVIEW are executed manually or from a running program.
  • If VIEW or AVIEW will pause there is a significant difference vs the original behaviour, executed within a program they either should (F21 set) print or stop execution or (F21 clear) do not stop execution.
  • A pause does not require a R/S to continue execution. It just goes on after the pause of one second or so.
  • May be it is advantageous to describe only the difference vs the original behaviour. If then still remains a lot to describe, it is a big difference and may be an issue. Or a subject missing in the emulator description.
HPMike
Posts: 439
Joined: Fri Jul 21, 2017 11:01 pm
Location: DFW, Texas

Re: Using VIEW and AVIEW on the DM41X

Post by HPMike »

Thomas Okken wrote:
Mon Oct 26, 2020 8:01 pm
I believe VIEW and AVIEW also halt program execution if the 82143A is connected but turned off. Note that flag 55 is set in this case.
Maybe the DM41X just needs a menu setting to emulate the "printer off" state?
I just confirmed this with my HP-41CV and HP 82143A printer. And yes, both flag 21 and flag 55 were set. So, there must be some two way communication between the printer and calculator that allows the calculator to determine that the printer is powered off. I think the IR communication is one way, so the calculator has no way of determining the printer's power state.

OK, so I just pulled out my 82143A Printer Owner's Handbook, and on page 29 it states that in this case with both flags 21 and 55 set and the printer OFF, that print functions result in the message PRINTER OFF and VIEW and AVIEW perform their normal functions and halt execution. Also ADV is ignored.
Last edited by HPMike on Mon Oct 26, 2020 11:23 pm, edited 2 times in total.
DM15L, S/N 00548. DM42, SN: 00159. DM41X, SN: 00973. DM32, SN 00054.
HPMike
Posts: 439
Joined: Fri Jul 21, 2017 11:01 pm
Location: DFW, Texas

Re: Using VIEW and AVIEW on the DM41X

Post by HPMike »

Amphitryon wrote:
Mon Oct 26, 2020 8:20 pm
HPMike wrote:
Mon Oct 26, 2020 6:34 pm
[...] 1) There is no printer plugged into the calculator, in which case flag 55 is clear. In this case, VIEW or AVIEW will pause to display the result, and resume execution when R/S is pressed.
  • Are you about to rewrite the manual? Then you should be precise, it makes a difference if VIEW and AVIEW are executed manually or from a running program.
  • If VIEW or AVIEW will pause there is a significant difference vs the original behaviour, executed within a program they either should (F21 set) print or stop execution or (F21 clear) do not stop execution.
  • A pause does not require a R/S to continue execution. It just goes on after the pause of one second or so.
  • May be it is advantageous to describe only the difference vs the original behaviour. If then still remains a lot to describe, it is a big difference and may be an issue. Or a subject missing in the emulator description.
1) I am only talking about VIEW and AVIEW executed within a program.
2) I should have said "halt" rather that "pause" execution. This requires a R/S to resume.
3) I was not attempting to explain the differences between original HP-41C vs DM41X behavior, but just how it works in general for all platforms.
4) The reason for all this is clear up some confusion about how someone proceeds on the DM41X when using VIEW and AVIEW in a program, since it emulates the HP 82143A plug-in printer but actually operates the HP 82240B IR printer.
Last edited by HPMike on Wed Oct 28, 2020 3:53 am, edited 1 time in total.
DM15L, S/N 00548. DM42, SN: 00159. DM41X, SN: 00973. DM32, SN 00054.
Amphitryon

Re: Using VIEW and AVIEW on the DM41X

Post by Amphitryon »

HPMike wrote:
Mon Oct 26, 2020 10:45 pm
4) The reason for all this is clear up some confusion
In public? :mrgreen:

So VIEW and AVIEW are understood now, how about PRPLOT mapped from 82143A to 82240B IR printer. Does it look similar as shown in the manual? Or the attached print out? If yes, hats off! then swissmicros (assumedly David) cared for the details.
prplot.gif
prplot.gif (1012 Bytes) Viewed 1863 times
Edit: corrected no. of IR printer.
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