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Some new user DM42/HP42s programming questions
05-16-2019, 01:42 AM (This post was last modified: 05-16-2019 01:56 AM by gomefun2.)
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RE: Some new user DM42/HP42s programming questions
I'm probably not the best person to answer these questions, because I just started to play around with the graphics myself.

But this is the manual for the dm42:
There are 3 main graphics modes:

Graphics Mode (read-write) — RCL "GrMod" retrieves the current graphics mode and STO "GrMod" sets the graphics mode to the number present in the X register. Graphics modes currently supported are:

0 = standard HP-42S resolution 131x16

1 = reserved for future use and maps to 0 on the DM42

2 = DM42 full resolution 200x120

3 = DM42 full resolution 400x240

so basically you store 0, 1, 2, or 3 into a variable called GrMod. This variable is a hidden variable that has a pre-determined meaning to the calculator.

As a side note, there are a ton of demo programs written by other people built into your calculator already. Just make sure you are on the most recent firmware.

They can be found in SETUP>FILE>LOAD PROGRAM. Once you load them, you can find them in XEQ, or edit them in PRGM as a normal program.

some graphics examples are like dplot and HPLOT.

here is a video of dplot:

PIXEL and AGRAPH are not limited to the original HP-42S’s resolution of 131x16 pixels. The compatibility with negative values to display lines and with complex numbers and matrices is conserved. You can now use horizontal values of 1≤X≤200 and vertical values of 1≤Y≤120 in 200x120 mode, or 1≤X≤400 and 1≤Y≤240 in 400x240 mode. Switching between 131x16, 200x120 and 400x240 modes is achieved using the GrMod virtual variable and current graphics resolution could be probed by ResX and ResY.

Free42 manual (the software the calculator uses):

has a list of commands starting page 28

look for the section:

Why does my HP-42S program not work properly in Free42?

some additions over the original hp42s are local variables and recursion, though I can't remember if those are yet updated to the dm42 firmware as they are new features. You can also change the font and font size (there are two different fonts), and also put underlines on the screen for easier reading of the text. Another difference is the dedicated soft keys on the dm42, and the instruction manual can be found built into the calculator, though that doesn't really change much.

I think this sort of answers some of your questions. Probably someone else can give a better answer.
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RE: Some new user DM42/HP42s programming questions - gomefun2 - 05-16-2019 01:42 AM

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