Temperature Indicator Usage

[towlerg]

Hi

had a quick at the datasheet, looks like an interseting device. But did you see the errata, oh dear.

You certainly need to set ADCON0 = x11101xx (x - not relevant) Fig16.1 "Temp indicator" input to ADC multiplexor

You need to turn on TSEN (which you have done)

And as the datasheet says

The temperature sense circuit is integrated with the Fixed Voltage Reference (FVR) module

maybe you need to turn that on as well,
so FVRCON = 1x1xxxxx

George

[Tabsoft]

Also the DS refers to a separate Application Note regarding this. AN1333

[gunayburak]

Also the DS refers to a separate Application Note regarding this. AN1333

The application note is but a general calibration and formulation for pic families that posses such a function , there is no information in that A.N. regarding configuration of the module ...

[gunayburak]

You certainly need to set ADCON0 = x11101xx (x - not relevant) Fig16.1 "Temp indicator" input to ADC multiplexor

I've seen the published ERRATA for 1827 thus the missing TSEN - TSRNG bits in the original datasheet yet what you suggest with the sentence that starts with "certainly" is completely wrong .. Is it not the point why we use a compiler language that connects the holding capacitor to the "Analog Channel " / and the automatic control of the GO/DONE bit and those all other things that is required for a proper operation of an ADC conversion in a single line with single command for us ? AKA ADCIN? As you may know the usage of the ADCIN command we have to first select a channel and state a variable for the incoming result to be stored , in this manner which is the channel 29 which I've already put in the code .. Configuring the ADCON0 CHS<4:0>bits doesn't do any favor to us except stalling the MCU for one more instruction cycle ..

Second of all about your idea of setting the FVRCON.7 enable bit doesn't make any sense , If you've observed the original datasheet page 137 the temperature indicator module's positive power supply can not be chosen and uses the VDD directly ...


But thanks for your approaches anyway ...

[towlerg]

I've seen the published ERRATA for 1827 thus the missing TSEN - TSRNG bits in the original datasheet yet what you suggest with the sentence that starts with "certainly" is completely wrong .. Is it not the point why we use a compiler language that connects the holding capacitor to the "Analog Channel " / and the automatic control of the GO/DONE bit and those all other things that is required for a proper operation of an ADC conversion in a single line with single command for us ? AKA ADCIN? As you may know the usage of the ADCIN command we have to first select a channel and state a variable for the incoming result to be stored , in this manner which is the channel 29 which I've already put in the code .. Configuring the ADCON0 CHS<4:0>bits doesn't do any favor to us except stalling the MCU for one more instruction cycle ..

Sorry, I've read this twice and I still don't understand. The multiplexer feeds the ADC with which ever input you select. You use ADCON0 to select the required input to the multiplexor.



My suggestion that the FVR module may need to be enabled has nothing to do with Vdd - the manual states that the temperature indicator is part of the FVR module and FVREN controls the FVR module (FVREN is FVRCON.7)



Sadly, I think this is ultimately a waste of time, without 2 point calibration the indicated temperature is "all over the place" and really only suitable as an overheat warning - just my 2 cents.

George

[gunayburak]

Sorry, I've read this twice and I still don't understand. George

What you do by configuring the ADCON0 CHS<4:0> bits is already done by the number written in bold format ---> ADCIN 29,VAR [29 refers to Temperature Indicator Already]
According to your claim : Each time you would like to get an ADC operation on different channels you first have to change the ADCON0 ? The answer is A NO ..
Because the PicBasic command does it for us ...

Have you seen anything associated in the diagram below that has anything to do with the configuration of the module except TSEN - TSRNG bits ? If there was there would be other registers shown out there ...

Sadly, I think this is ultimately a waste of time, without 2 point calibration the indicated temperature is "all over the place" and really only suitable as an overheat warning - just my 2 cents.

I don't think it is a waste of time at all and that's why I'm craving to solve this issue ...

[towlerg]

Aw well, each to his own.

George

[gunayburak]

Anyone has an idea ?