hi,
I want to send data through SPI (chip select active low) port using EDMA 5 bytes at a time, the amount of data is [160][15].
at first to test that my code is working I set Acnt =1 , Bcnt=480, and it seemed all fine.
however; when I set the true values Acnt=5, Bcnt=480, I get a very strange signal on the osciliscope, moreover data is shifted in the positive period of chip select.
when I change Acnt to 3, spi out puts two consectuive bytes, and when Acnt=3 chip select remains inactive (positive) while data is outputed byte by byte.
my questions as follow:
- what is the best Acnt and Bcnt values to setup yhe trnsfer.
- how Acnt values affect SPI transmission.
-how chip select signal is being controlled in EDMA mode.
-can chip select be manually controlled while in EDMA mode, if so how to synchronize it with the trnasfere.
- I enabled the transfer complete interrupt, and its being latched in the IPR, while the CPU can't see it.