ADC values in graph- F28335- CCS4

Hi Mahesh,

I am not sure how to interpret the vertical scale on your graph, can you show it in the range of raw ADC conversions: 0 to 4095?  

Hi Devin

I dont know how to get in those scale.I hav directly plotted the following address:

regards

Mahesh

The result registers you are looking at there are left aligned, so 48 is 0x0030 = 3 LSBs above 0V.  This is within reason for what might be expected when sampling ground.   

Hi Devin

How can i make it to proper values(other than left aligned)?

Also how to obtain the graph for that?

regards

Mahesh

The best way to get right aligned values are to use the AdcMirror registers, which are the same as the result registers, just right aligned.  You can also use a right shift on the result registers: ADCRESULT0 >> 4

As far as graphing, I am not sure exactly, but I think you will want to run some code to perform sampling which moves each sample to an array in memory, then graph that array.

Hello Mahesh!

You read: "the graph when ADC pins are grounded".

1 Your digital ground and analog ground are separated or aggregated? The result would be better if they are separated.

2 On my opinion "3 LSB" is too much for the ADC-noise. It should be no more "2 LSB".

3 I think it will be helpful for you http://e2e.ti.com/support/microcontrollers/c2000/f/171/p/264395/932865.aspx#932865.

Regards,

Igor

Hi Mahesh,

To be precise,  please implement the following:

Voltage1 =((AdcRegs.ADCRESULT0>>4) );

and add Voltage1 to watchpoint and plot the graph for this variable.

Regards,

Gautam Iyer