I'm having some trouble communicating between a 16F877 and an Atmel =
AT45DB021 Dataflash using the CCS C compiler and wonder if anyone has =
seen the same problem.

If I bit-bang the SI, SO and SCLK lines, no problem -- but if I try to =
use the CCS compiler's hardware SPI commands they don't seem to work. =
Specifically, I'm able to use the CCS commands to spi_read() and =
spi_write() using the DataFlash's two internal buffers. Reading =
Dataflash main memory is another story. Also, I've experimented and it =
doesn't appear to be a power problem. Furthermore, I've experimented =
using maximum delays and polling the SPI register for data, with no =
success. What has worked is sending and extra don't care byte to the =
DataFlash, but the Dataflash's datasheet doesn't request this, and I'm =
not sure why it works (clock-edge?).

If any Piclisters have faced this problem, any help would be =
appreciated.

Thanks, Shawn

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