Could someone please point to a good site on learning more about SPI between AT89S53 controllers. I am building a robot with the "brain" as one controller reading sensors through extra port through memory.
The problem is the motors are being controlled by another AT89S53 and I need to send a command to it through SPI communications. I have set it up and pulled a pin low to select the processor but, it does not look like my command is being sent through the SPI when I put on a scope. The clock on the SPI does not look like it is pulsing eather.
let me know if you would to see the code, or just point me a site so I can better understand SPI.
Thank you, dave