Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Signed fractional format ADC dspic33EV

Status
Not open for further replies.

electronicsman

Full Member level 5
Joined
May 4, 2012
Messages
291
Helped
11
Reputation
22
Reaction score
12
Trophy points
1,298
Activity points
3,737
I am referring to the microchip dspic33ep micro controller. I am trying to read the adc of the pot, the adc is initialized for signed fractional format and in the data sheet it is shown as signedFractional.JPG. The test point at POT reads 3.3V and when i debug the variable is 32736 which when converted into binary will be
Code:
 0111 1111 1110 0000
My first doubt is the number of zeros are 5 but in the data sheet image is should be 6. Why is the difference?
Second doubt i want to get the original voltage at the ADC of X (32736) value, i will right shift X by 6 bits. 512 value corresponds to 3.3V then X >> 6 correponds to what voltage? (X >> 6) * 3.3/512? Am I correct and any other methods available? Please advise.
 

Exactly which MCU do you have (you have mentioned dsPIC33EV and dsPIC33EP - but the next characters may or may not be significant)?
Do you have it set for 10-bit or 12-bit? Showing us the configuration for the ADC would help here.
AS for how to interpret the value, have you looked at the ADC FRM section that is appropriate for your device?
Susan
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top