Kinetis MicrocontrollersのトピックRe: ADC mux on K20

ADC mux on K20

kevinmc — Tue, 26 Nov 2013 15:04:55 GMT

Hi All,

I have a K20DX512 device configured and reading accurately from ADC0.

However, I would like to read multiple channels at once, or a group of channels (i.e. x4) and interupt only when the four ADCs have succesful conversions in place.

I am guessing this is done by assigning the required ADC channels to a ADC MUX function? I am struggling to source much documentation on this, the data sheet seems only to refer to the MUXSEL bit.

Can anybody point me in the direction of assigning a channel 'set' to a ADC MUX mapping and how to configure for this process. Any links to documentation, etc would be gerat.

Thanks in advance,

Re: ADC mux on K20

kevinmc — Tue, 26 Nov 2013 21:25:29 GMT

I think my understanding of the MUXSEL bit is incorrect, correct operation and usage is covered here:

ADC on FRDM problem.

I can write something to sequence the ADC measurements, however it would be nice to set away multiple conversions at the same time - if anyone has info on initiating this please give me a heads-up.

Cheers,

Re: ADC mux on K20

Hui_Ma — Wed, 27 Nov 2013 05:54:17 GMT

Kinetis ADC module can only do a channel conversion at one time, not multiple channels simultaneously.

There is an application note AN4590 about using DMA to Emulate ADC Flexible Scan Mode on Kinetis K Series.

More detailed info, please check below link:

http://cache.freescale.com/files/32bit/doc/app_note/AN4590.pdf

http://cache.freescale.com/files/32bit/doc/app_note/AN4590SW.zip

Wish it helps.