Correcting ADMUX selection in __analogRead()

[LaZsolt]

• ADMUX input source used a wrong mask. (was 0x0f instead 0x1f)
• LGT8F328D ADMUX has less input than P version. If someone want to read these unselectable inputs, it will return zero ADC value.
• V5D1 and VCCM is same input with different name

[LaZsolt]

Set default analogReadResolution to 10 bits.
#41

[LaZsolt]

Unnecessary round bracket deleted.

[frizzle101101]

is this why I'm getting 12bit default adc on projects

[dbuezas]

Hey @LaZsolt !
This will be a breaking change, right? (10bt analg read by default)
I'll then release an intermediate version before, and then another one with this as v2.
Do you mind adding a small example sketch to switch between analogRead resolutions?

[LaZsolt]

This will be a breaking change, right?

Yes, but as @jayzakk mentioned in #41 the aduino default is 10 bits for backward compatibility with AVR based boards.

I think not necessary any example sketch, because it is a normal Arduino analog API extended function for those boards which have 12 bits ADC.
Documentation: https://www.arduino.cc/en/Reference.AnalogReadResolution

It may be unpleasant for those users who will be upgrading dbuezas/lgt8fx core.

[dbuezas]

Gotcha. I'll make a release without, and then merge this one and move to v2 following semver

[LaZsolt]

But this request is not mainly about AnalogReadResolution.

In this line below, because of the bitmask of pin variable, only 8 analog inputs reachable. (A0 - A7)

lgt8fx/lgt8f/cores/lgt8f/wiring_analog.c

Line 147 in 97e273a

ADMUX = (analog_reference << 6) | (pin & 0x07);

With my correction more inputs will be readable: PIN_A8, PIN_A9, PIN_A10, PIN_A11, IVREF, AGND, DACO, 1/5 AVCC, 4/5 AVCC

[dbuezas]

Oh, so this is not breaking change then. Should i merge now?

[LaZsolt]

This pull request is two in one.
1st - expanding ADMUX pin select bitmask from 0x07 to 0x1F
2nd - changing the default resolution of analogRead() to 10 bits for Arduino compatibity reason.

• So to get back the LGT8Fx 12-bit ADC capabilities, must change the resolution to 12 with AnalogReadResolution(12);. (At least in the setup function.)

I think it's acceptable. If you think the same then you should merge it.

[dbuezas]

Oh got it. Then Ill hold it a bit and very soon make 2 releases. The first without and the second with (and that will be v2.0.0)

[navr32]

So this is the problem says why my A8 pin of wavgat board reject at build ?
Arduino : 1.8.15 (Linux), Carte : "LGT8F328, Default (64), Internal, 32 MHz, 328P-LQFP32 (e.g. MiniEVB nano-style and WAVGAT)"

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'A8' was not declared in this scope

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[LaZsolt]

@navr32
In LGT8F328P-LQF32 the A8, A9 and A11 analog inputs not connected to any pins. That's why not declared.
I assume the A8 name is wrong on the WAVGAT board. The real name coud be A6.

[navr32]

Hi LaZolt !
You assume very well ! I just come to test it and this is A6 so simple ...very annoying i haven't think to this..many thanks.

[LaZsolt]

Close this request, because #217 include the solution.