ADC->FX3 send only alternate samples

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fventuri
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I am working on a project where we would like to connect an ADC directly to the FX3 and send to the host only alternate samples (i.e. every other sample); for instance the GPIF II PCLK would be running at 100MHz, but the samples sent to the host would be at a rate of 50MHz.

Is this possible using the GPIF II state machine? If so, do you know of a similar project to see how they did it (without using an FPGA)?

Thanks in advance,

Franco

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Chaithra_p
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Hello @fventuri ,

 

Alternate sample means I think you are saying that FX3 has to read data in alternate clock cycles (i.e., for example, Fx3 should not read first clock cycle data, it should read 2nd clock cycle and so on) if my understanding is correct then it can be done by using GPIF state machine. You have to make transition between two states like below.

Chaithra_p_1-1698647059399.png

 

And we don't have any similar example project for this. You can refer to any of gpif example which is there in SDK folder.

 

 

Thanks & regards,

Chaithra

 

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Chaithra_p
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50 solutions authored First like given 25 solutions authored

Hello @fventuri ,

 

Alternate sample means I think you are saying that FX3 has to read data in alternate clock cycles (i.e., for example, Fx3 should not read first clock cycle data, it should read 2nd clock cycle and so on) if my understanding is correct then it can be done by using GPIF state machine. You have to make transition between two states like below.

Chaithra_p_1-1698647059399.png

 

And we don't have any similar example project for this. You can refer to any of gpif example which is there in SDK folder.

 

 

Thanks & regards,

Chaithra

 

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Thanks for the suggestion Chaithra.

To confirm my understanding (I am fairly new to the FX3), if I want to read alternate samples until a certain limit because of the size of the DMA buffer, I should be able to run a state machine with states like this:

 

state_machine.png

where the 'READ' state has the setting 'Repeat actions until next transition' turned off.

Thanks again,

Franco

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Chaithra_p
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50 solutions authored First like given 25 solutions authored

Hello @fventuri ,

 

That state machine is correct, but Can you let me know how you will comeback from READ_DONE state..?

 

 

Thanks & regards,

Chaithra

 

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