Other Parts Discussed in Thread: ADS1278, TMS320C28346
Hi there!
I am using the ADS1278 in combination with the TMS320C28346 control card. Both communicate via SPI. The issue I am having is:
Since the ADS1278 is the slave it get's its clock from the TMS320. This does also mean, that the first two bits (depending on which edge data is shifted out) are none sense and have nothing to do with the data produced by the ADS. Additionally I have to turn on the SPICLK 8 cycles longer to make sure all data is shifted in - this means I am getting 6 bits at the end of the data chain.
How can I access my data by every bit I have? The idea is to have a defined data length (for example, using 5 channels at 24 bit means a data length of 120bit). Now a variable i is counting from
i = 0...(120-1)
starting a the third bit of the data coming in. This means, the first two bit are neglected and it stops after 120 bit also neglecting the last 6 bit.
Another option (which I am following right now) is to move the whole data to the DSP in arrays of the same width (16 bit) as the SPIRXBUF. Here, I also need to "cut" the first two and the last 6 bit and shift the whole set of data to another memory.
How can I access my data like described? Has anyone faced this issue as well and how did you solve it?
Thank you very much in advance,
Johannes