External Mux Continued

After exporting the design to SDK and importing Adam Taylor's Software Files, we can now import a signal (voltage).

First we must modify Adam's .h and .c files to read the VP and VN.


In helloworld.c change:

 XSysMon_SetSeqChEnables(SysMonInstPtr,
                                             XSM_SEQ_CH_AUX00|
                                             XSM_SEQ_CH_AUX08);
to...

XSysMon_SetSeqChEnables(SysMonInstPtr,
               XSM_SEQ_CH_VPVN
);

AND

XADC_Buf_Ch1[samples] = XSysMon_GetAdcData(&SysMonInst, XSM_CH_AUX_MIN);

to...

XADC_Buf_Ch1[samples] = XSysMon_GetAdcData(&SysMonInst, XADCPS_CH_VPVN
);

In xsysmon.h we need to add the following to define our new command:

#define XADCPS_CH_VPVN        1

**Refer to  Emily's post, "XADC Pinouts for the External Mux (XADC Header)" for extra help.


Adam Taylor suggested that we should try inputting a voltage between 0.3V and 1.0V

To do this, we created a voltage divider on a proto-board with an output of 0.625V. We then connected this voltage to the VP and VN pins of the XADC Header on the Zedboard and connected the three grounds of the XADC Header to ground on the proto-board as well.



**********************************************************************************
We have decided to move on from this project into the ad9467 FMC. Hopefully we will be able to complete it another time when we have more answers to our questions.

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