SOI interface question

Forum 2005-2010 (read only) General Frequently-Asked Questions
1

how many different devices can you run from one SPI interface on the MEGA 1280? I have looked around and found no info on this topic.

Thanks in advance

Dillon

2

In theory an infinite number because you just keep enabling the different devices separately.

In practice there is a limit imposed by the fan out of the pins, that is how many inputs it will drive. This is in turn determined by the fan in of the devices you want to use. 'Fan in' is the input load presented by a device and changes depending on the device and technology it is fabricated with.

3

Thanks Mike,
That helps. I was worried that it was only one but now that I know I can handle a few connections it simplifies things..

thanks again

Dillon

4

Clock and data lines are shared, but you need a separate chip-select for each device with SPI, right?