ABSTRACT
GENERAL PURPOSE INPUT/OUTPUT (GPIO) FUNCTIONALITY
3.1 Pin Multiplexing (MUX) and General Purpose I/O Overview
Due to the limited number of physical pins on the LF2407 DSP, it is necessary to multiplex two functions onto most of the pins. That is, each pin can be programmed for either a primary or secondary (GPI/O) function (see Fig. 3.1). Once the pins on the LF2407 are multiplexed, the effective pin-out of the device is doubled. This provides enough effective pin-out for six General Purpose Input Output (GPIO) ports to be configured as the secondary function on most pins. Each Input/Output Port (IOP) consists of eight pins when they are configured to their secondary function.
