Simultaneous sampling of 12 ADC channels in K22F

[prasannanaik]

Hi ,

I want to use K22F series controller in a control application wherein i need to sample 12 ADC  channels on one trigger.

Basically i want a 625 usec timer to trigger the ADC and ADC should sample all the 12 channels and then i should get the ADC interrupt(only one interrupt) on completion of sampling of all the channels. I couldn't find such feature in K22F. Please help in writing driver for this application. 

I have FRDM K22F board for evaluation.

Please help.

Thanks and best regards,

Prasanna

[Robin_Shen]

Hi Prasanna,

Please refer: Using DMA to Emulate ADC Flexible Scan Mode with SDK 2.x

Best Regards,

Robin

-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

[prasannanaik]

Hi Robin,

   Thanks for your input. 

   In the application expalined in the attached link, a LPMTR timer interrupt is required to sample each channel. So to sample 3 channels we need 3 triggers of LPMTR which is not acceptable in my case. I need an application as shown below:

Please help in modifying the drivers for the same.

Thanks and best regards,

Prasanna

[mjbcswitzerland]

Hi

Each ADC can sample one input at a time - parallel sampling is not possible at a single ADC.

To sample 12 inputs with one interrupt on completion can be done using DMA, where the first sample is started and on completion a DMA transfer is triggered to load the next channel to be sampled, and so on until the required number of samples have been collected. The sampling is of course sequential and not parallel but one end of sequence interrupt is possible.

Regards

Mark

Complete Kinetis solutions for professional needs, training and support:http://www.utasker.com/kinetis.html
Kinetis K22:
- http://www.utasker.com/kinetis/FRDM-K22F.html
- http://www.utasker.com/kinetis/TWR-K22F120M.html
- http://www.utasker.com/kinetis/BLAZE_K22.html
- http://www.utasker.com/kinetis/tinyK22.html
uTasker: supporting >1'000 registered Kinetis users get products faster and cheaper to market
Request Free emergency remote desk-top consulting at http://www.utasker.com/services.html