HP-41 Halfnut constrast setting

HP-41 Halfnut constrast setting - Printable Version

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HP-41 Halfnut constrast setting - hth - 11-02-2020 05:49 PM

I know there are functions around to fiddle with this nibble, I am wrote some myself long time ago. What I wonder is, what is the preferred way of doing it today? Having functions or a mode/means to press plus or minus key to adjust it, what is around?

RE: HP-41 Halfnut constrast setting - CY-CL - 11-02-2020 06:02 PM

In the HEPAX module is a funtion called CTRAST to setup the contrast.

RE: HP-41 Halfnut constrast setting - Garth Wilson - 11-02-2020 07:31 PM

I've never had any reason to change it; but is there a way to do so with synthetic programming, or with something like the ZENROM's RAM editor?

RE: HP-41 Halfnut constrast setting - Didier Lachieze - 11-03-2020 08:39 AM

(11-02-2020 07:31 PM)Garth Wilson Wrote: is there a way to do so with synthetic programming, or with something like the ZENROM's RAM editor?

I don't think so, on my 41CX halfnut I found that the contrast was a bit low so I adjusted it with the functions from the Sandmath module which were initially published in HPX V1N6p8 by Michael Katz:

CTRST [Set Display Contrast]
CTRST? [Find Display Contrast]
CNT+ [Increase Contrast]
CNT- [Decrease Contrast]

Having a way to increase/decrease the contrast as on the Pioneers makes it easy to adjust to the correct value, but on my 41CX, once adjusted I didn't had to change it again. So I would say it's useful but rarely used.

RE: HP-41 Halfnut constrast setting - Ángel Martin - 11-03-2020 01:22 PM

with value in X: (between 0 and 15)

Code:

094    "T"    

013    "S"    

012    "R"    

014    "T"    

003    "C"    Michael Katz

0F8    READ 3(X)    

38D    ?NC XQ    

008    ->02E3    [BCDBIN]

0A6    A<>C S&X    

130    LDI S&X    

010    CON: 16    

306    ?A<C S&X    

01F    JC   +03    

085    ?NC GO    

0A2    ->2821    

270    RAM SLCT    

3F0    PRPH SLCT    

0A6    A<>C S&X    

168    WRIT 5(M)    

149    ?NC GO    Select Chip0

026    ->0952    [ENCP00]

RE: HP-41 Halfnut constrast setting - dmh - 04-13-2022 07:27 AM

If you're interested in seeing the different halfnut contrast settings before investing the time and effort to get a program working to set it, I captured all the settings below.