AnsweredAssumed Answered

AD5934 reading status register

Question asked by Iouri on Sep 11, 2017
Latest reply on Sep 19, 2017 by musach

Hello,

 

I am working with AD5934 and having problem with read values from the status register. I am following flow chart from AN 1252. First, I read status register to see of data is ready if data is ready I am reading data to the buffer. Than I am reading status register again to see if sweep is complete.  If sweep is not complete I am sending command to increase frequency.

 

For debug purposes I am counting number of data reads, ie if data is ready I am reading data and increment counter. I also storing  value from status register (ie when I am hunting for data  ready flag)  when data is ready and second reading from the status register (when I am determining if scan is complete) and storing both of those values in to array. 

 

I have set start frequency 5KHZ increment frequency 2KHZ and number of steps 5.

 

Once I run the code I am getting large number of readings from the status register, around 50, and this number is changing from one code execution to another. but my output frequency from DDS after scan is complete  is correct 15KHZ.

 

bellow the readings from the status register, left column is first reading ie when hunting for data ready and second column is second reading when determining scan complete.

 

Any word of advise.

 

 

Thank you,

 

Iouri

 

Sweep Complite 50
03 70
03 70
FF 70
C3 70
FF 70
36 70
FF 70
F6 70
FF 70
FF 70
FF 70
CF 70
52 70
1E 70
2A 70
F3 70
02 70
02 70
02 70
02 70
02 70
02 70
02 70
02 70
02 70
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03 70
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03 70
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FF 70
FF 70
97 70
46 70
FF 70
FF 70
FE 70
FF 70
FF 70
FF 70
FF 70
C6 70
B7 70
FF 70
FF 76


Sweep Complite 51
FF 70
FF 70
FF 70
5F 70
FF 70
CE 70
1B 70
FF 70
FF 70
FF 70
96 70
F7 70
12 70
F7 70
FF 70
FF 70
02 70
02 70
02 70
02 70
02 70
02 70
02 70
02 70
02 70
02 70
03 70
03 70
03 70
03 70
03 70
03 70
03 70
03 70
03 70
03 70
1A 70
F6 70
FF 70
FF 70
2F 70
FF 70
FF 70
FF 70
FF 70
FF 70
D6 70
FF 70
F2 70
0A 70
76 76

Outcomes