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I have a 12-bit ADC that I want to filter using a DFB and then (for test purposes) output to an 8-bit VDAC. (I want the 12-bit ADC to get a reasonable resolution on my signal and I don't really want to drop down to 8-bits. The VDAC output is only for initial testing purposes as I really want the output of the DFB so I can output it on an OLED display so the more bits the better
All of the examples I can find use an 8-bit ADC when using DBA to the DFB. (I've looked in the examples projects, on the Cypress web side and used Google.)
I must admit that I do find the DFB datasheet a little confusing at the moment - perhaps when I understand what it is actually saying then it might make sense.
I can use the CPU to read the ADC and write to the DFB and similarly read the DFB holding register and write a shifted value to the VDAC but I really want to know how to set up the DFB to accept a 12-bit value via DMA into the staging registers.
PSOC 5LP on an -059 kit.
Thanks
Susan
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Thanks Keerthi - From that I was probably not that far out (still don't know why the DFB only ever output a value of 0x01!) but it is good to see a 'real' example that I can work from.
Susan
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All you need to take care is coherency, data align bits and read/write pointers. Data align is required if you are doing 2 byte transfer.
Page 24, 25, 26, 27 of the filter component datasheet talks about this.
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The DMA transfer works nicely now - thanks Keerthi.
Susan