about SPI!

[gas]

hi,
i want to make two atmega8 communicate by SPI, and one is master. i'll send four bytes in main(), and receive four bytes in the interrupt, is that ok?

thank you!

 

[pike]

Yeh that sounds fine. What kind of speeds are we talking about?? You could just send the bits 1 at a time, instead of 4 at a time.

What do you want to send through this interface. There might be an easier way.

 

[plot]

are you doing this in AVRStudio, or some C variant like WinAVR or CodeVision?

 

[gas]

Yeh that sounds fine. What kind of speeds are we talking about?? You could just send the bits 1 at a time, instead of 4 at a time.

What do you want to send through this interface. There might be an easier way.

thank you, Pike!
you mean i could define a variable to count the bytes, but transmit one byte at a time,of course i should divide the byte into 8 bits,right?

 

[gas]

are you doing this in AVRStudio, or some C variant like WinAVR or CodeVision?

hi, Plot!
i did it in ICCAVR!

 

[pike]

[ you mean i could define a variable to count the bytes, but transmit one byte at a time,of course i should divide the byte into 8 bits,right?

Yes, you have to break the byte up into 'bits'. But your initial proposal was to break the file up into 2 smaller chunks (of 4 bits) and send and send each chunk one at a time.

You could just break it up into 8 smaller bits and send it. It's just slower but requires less output pins.

 

[gas]

thank you, Pike,i ll try it.