AN555 - Microchip

AN555 Software Implementation of Asynchronous Serial I/O

of these bits in the Serial Status/Control Reg table given later). Summary of PutChar function: 1. Make sure _txmtProgress & _rcvOver bits are cleared 2. Load TxReg with data to be transmitted 3. Call PutChar function Receive Mode The reception mode implementation is slightly different from the transmit mode. Unlike the transmit pin (TX in the example code i.

Features

N A half duplex, interrupt driven, software implementation of RS-232 communications, using a PIC16C71, is described in detail below. The transmit pin used in the example code is RB7 and the receive pin is connected to the RA4/T0CKI pin (Figure 2). Of course these pins are connected with appropriate voltage translation to/from RS-232/CMOS levels. Schematics describe the voltage translation in the hardware section of this application note. Transmit Mode Transmit mode is quite straight-forward to implement in software using interrupts. Once input clock frequency and baud rate are known, the numbe.