DM42 Display Control Tutorial

[jjohnson873]

The new DM42 has such a beautiful display with the capabilities that far surpass any other calculator short of the HP Prime. I've poured through the HP42S manual, the HP42S programming manual, the free 42S manual along with DM42 Users Manual. The commands are available for display control using CLLCD, VIEW, AVIEW, PIXEL, AGRAPH, GrMod and flags 34 & 35. I'm working through Bill (Smithville NJ)'s post on "Displaying String on Free42 & DM42 so I can understand the ways to take complete control of the DM42 display at each resolution (up to 400x240). What I'd like to see is someone write a DM42 display control tutorial, beginning with some simple example programs and ending up with something like Bill's completely new font set. I had written a program to output some values using AVIEW. While this gives me the values and a string in the upper portion of the DM42 display, it still displays the X, Y, Z and T values. I'd prefer to clear the X,Y,Z, T values from the display and just display the string value or any other output from the program I'm running. Once exiting the program, I'd like to return to the normal 4 value stack (X, Y, Z, T) display.

Am I missing something simple on DM42 display control? I'm still experimenting with flags 34 & 35 and perhaps therein lies the answer to my problem.

[revwillie]

(03-25-2018 03:57 PM)jjohnson873 Wrote:  Am I missing something simple on DM42 display control? I'm still experimenting with flags 34 & 35 and perhaps therein lies the answer to my problem.

I agree with you if you are saying that it's a pain to gather together the known info in one place. This is further complicated by the friendly banter that most threads evolve into.

It's all about the virtual variables. If you haven't read that part of the built in quick reference guide or the online manual, make sure you do. One thing you seem to be asking is if you can hide the stack when the classic HP resolution mode (GrMod=0) is chosen. I don't think that's currently possible but the stack display is hidden in the higher resolution modes. At that point, your output would just have to be generated by PIXEL or AGRAPH. Note that AVIEW or VIEW are for displaying in one space and PIXEL and AGRAPH display in another space where the two spaces do not overlap. I hope someone corrects me if I'm wrong, but I think PIXEL or AGRAPH overtakes the VIEW or AVIEW display in all modes when they are invoked.

The programs Bill shared are built upon the native AGRAPH if I understand correctly. I also have to do some reading to get up to speed on them. There is also some good stuff in THIS thread for line drawing. Starting on the simple end, I experimented with a modification to the DJPLOT program that comes preloaded in the DM42. In this post,I shared the 'test2' version and a primitive 'big dot' idea for plotting. I have yet to read if that idea was previously published in the WP43S user manual or otherwise borrowed.

So, taking 'complete control' of the display seems at this point to require drawing what you want in pixels or Alpha-encoded pixel groups. See the SMILE program in the original 42S manual as well as the HP logo program that appeared in the later programming manual. I think I read that there is a way to use matrices or complex numbers, too. I wish I had more time to delve into it.
The new display hardware is begging for more graphical exploitation, but the 42S was never a 'graphical' calculator.

And one last wrinkle: Free42 also has the virtual printer display capability. Several of us have wondered if that will appear later in the DM42. What is the mysterious GrMod=1 reserved for???

[Didier Lachieze]

(03-27-2018 01:21 PM)revwillie Wrote:  Note that AVIEW or VIEW are for displaying in one space and PIXEL and AGRAPH display in another space where the two spaces do not overlap. I hope someone corrects me if I'm wrong, but I think PIXEL or AGRAPH overtakes the VIEW or AVIEW display in all modes when they are invoked.

In the classic 42S display mode (GrMod=0), PIXEL and AGRAPH overlap with the AVIEW or VIEW display and can be used to add graphic elements as done with AGRAPH in the CIRCT program from the HP 42S Electrical Engineering Solutions:

   

When you do that on the DM42 the display mode switch automatically to graphic mode with the 42S font, even if you have selected the DM42 Sans font.
This is nicely managed by the DM42 firmware.

   

[revwillie]

Thank you, Didier. The screenshots are especially helpful. That's a feature I haven't figured out.

[grsbanks]

(03-27-2018 04:13 PM)revwillie Wrote:  Thank you, Didier. The screenshots are especially helpful. That's a feature I haven't figured out.

Hold down the shift key, press and release [E] (DISP). The DM42 will emit a quiet "shutter release" sound and the resulting .bmp file with a filename based on current date and time will be deposited in the /SCREENS directory of the calculator's FAT drive.

[jjohnson873]

I'm working through the manuals, examples, graphics and programs that the users have posted on the forums. Beginning to understanding the limitations, abilities and capabilities of the graphics of the DM42. Ran "Hello World!" and a Mandelbrot graph. Playing with GrMod modes 0, 2 and 3. Seems like there should have been a hires global font matrix embedded somewhere in the DM42, versus creating a matrix of fonts to hold characters for the higher resolutions screens. Thank you for the pointers, hints and responses, revwillie, Didier and grsbanks. I'm collecting a group of DM42 notes, programs, hints, thoughts and ideas on graphics. Finding time to publish a pdf is the challenge!

[Jake Schwartz]

(03-28-2018 03:29 AM)jjohnson873 Wrote:  I'm working through the manuals, examples, graphics and programs that the users have posted on the forums. Beginning to understanding the limitations, abilities and capabilities of the graphics of the DM42. Ran "Hello World!" and a Mandelbrot graph. Playing with GrMod modes 0, 2 and 3. Seems like there should have been a hires global font matrix embedded somewhere in the DM42, versus creating a matrix of fonts to hold characters for the higher resolutions screens. Thank you for the pointers, hints and responses, revwillie, Didier and grsbanks. I'm collecting a group of DM42 notes, programs, hints, thoughts and ideas on graphics. Finding time to publish a pdf is the challenge!

Do I detect a potential HHC2018 talk in the making? <hint, hint> :-)

[jjohnson873]

(03-29-2018 05:02 PM)Jake Schwartz Wrote:  Do I detect a potential HHC2018 talk in the making? <hint, hint> :-)

Jake...your perceptive abilities exceed your cinematographic excellence! ;-)