ADC in 12F683; puzzled

[mikebike]

Missing :

- Deactivate comparators

Is this specific for 10 bit ADC, or should it be there for 8 bit conversion as well?
And how? -CMON0 something?

Missing :
- ADC result right justified
Alain

Hm, the example programs that I have (for 16F877A) do not have such an instruction, does that PIC not need it?

ADCON0.7 = 1 seems to have have cured the problem, thanks guys.

[Acetronics2]

Is this specific for 10 bit ADC, or should it be there for 8 bit conversion as well?
And how? -CMON0 something?

have a look to datasheet ... Comparator section !!!

Hm, the example programs that I have (for 16F877A) do not have such an instruction, does that PIC not need it?

some pins share the comparator and ADC functions ... you HAVE to verify which function is deactivated and which is to activate. ( one at a time ... )

Depends on the chip used - and the ports used ...

ADCON0.7 = 1 seems to have have cured the problem, thanks guys.

Full config done = NO suprise ...

sometimes, the pic defaults @ reset are the ones you want ... sometimes not. so you have to verify everything with the pic Datasheet !!!

[mikebike]

have a look to datasheet ... Comparator section !!!

Done that, but didn't understand it (new to this stuff).

CMCON0 = %00000000

seems to be accepted by PBP and the chip (still) works.

[Acetronics2]

Done that, but didn't understand it (new to this stuff).

CMCON0 = %00000000

seems to be accepted by PBP and the chip (still) works.

Boooooooooooooo .... the chip is really gentle with you ...

look a bit closer at the drawings and the corresponding config @ $8 p 53 ...

Alain

[mikebike]

I said that I don't understand this kind of data sheet...

Well, I think it says that .....000 only turnes the comp output off, but ....111 turnes the comp off as well. It doesn't matter much for this project, but my first project is battery operated and saving some current is welcome.


I guess it's nice to have a comparator integrated, but right now I would need an OP-amp instead!

[Acetronics2]

I said that I don't understand this kind of data sheet...
!

I do promise you lots of fun ...

Swedish hot nights ... I believed it was a bit different

Alain

[HankMcSpank]

Not sure if you're sorted, but as someone who recently struggled with this very type of same thing, here are the 12F683 commands towards helping you out ...

If using 10 bit AtoD, then right justify is required**.....

ADCON0.7 = 1 (right justifies your 12F683 AtoD result)

.....whereas with 8 bit AtoD, left justify is required....

ADCON0.7 = 0 (left justifies your 12F683 AtoD result)

and finally this one....

CMCON0 = 0 (turns the pesky 12f683 comparator off - of course if you need the PIC's comparator, then it's not pesky at all & this command should not be used!)

Good luck!



** and no matter how many times I read the datasheet with respect to left/right justifying, I end feeling like an amoeba being wafted around the bottom of a refuse tip pond.

[mikebike]

sometimes, the pic defaults @ reset are the ones you want ... sometimes not. so you have to verify everything with the pic Datasheet !!!

Yes, I have had some interesting output signals on outputs that were not specified in the program!