9.6 Input Mapping

The inputs of the Peripheral Pin Select options are mapped on the basis of the peripheral. That is, a control register associated with a peripheral dictates the pin it will be mapped to. The RPINRx registers are used to configure peripheral input mapping. Each register contains sets of 8-bit fields, with each set associated with one of the remappable peripherals. Programming a given peripheral’s bit field with an appropriate 8-bit index value maps the RPn pin with the corresponding value, or internal signal, to that peripheral. See Table 9-3 for a list of available inputs.

Configuring UART1 Input and Output Functions provides a configuration for bidirectional communication with flow control using UART1. The following input and output functions are used:

• Input Functions: U1RX, U1CTS
• Output Functions: U1TX, U1RTS

//
*******************************************
// Unlock Registers
//*****************************************
__builtin_write_RPCON(0x0000);
//*****************************************
// Configure Input Functions (See Table 9-3)
// Assign U1Rx To Pin RP35
//***************************
_U1RXR = 35;
// Assign U1CTS To Pin RP36
//***************************
_U1CTSR = 36;
//*****************************************
// Configure Output Functions (See Table 9-6)
//*****************************************
// Assign U1Tx To Pin RP37
//***************************
_RP37 = 1;
//***************************
// Assign U1RTS To Pin RP38
//***************************
_RP38 = 2;
//*****************************************
// Lock Registers
//*****************************************
__builtin_write_RPCON(0x0800);