This is a follow to earlier, related post today: http://e2e.ti.com/support/microcontrollers/stellaris_arm_cortex-m3_microcontroller/f/471/p/644374/reply.aspx
Applicable: both M-3 and new M4F Stellaris devices.
The assortment and number of Peripheral Modules, Buses and/or Interfaces adds to the appeal of Stellaris MCUs. Our group is often size constrained - thus our current project employs a new, 64 pin M4F Stellaris. And - there are a great number of these desired peripheral modules, buses, interfaces - but we could not "assemble" all of our functional, peripheral needs and confine each function to its singular, dominant (in pin number) port. Thus we employed a pin "mix & match" - grabbing needed peripheral pins across multiple ports - with the goal to harvest the greatest number of total, needed peripherals. The flexibility this offers is terrific! In our case this method enabled us to "squeeze out" three (3) more peripheral functions than could be realized if drawing pins only from a common port. Great stuff!
Appears that SPI, CAN, UART, I2C, QEI and even PWM Generators (possibly USB too) all may employ this multi-port, pin selection, peripheral creation method.
Possible downside - possible speed or data penalties - our investigation continues in this regard and will report here should there be request/interest.
Note: Use of PinConfigure() and PinType() functions and the individual enabling of each port selected is required. Slight increase in effort/complexity yields large rewards...
