com_getchar

#include <net_config.h>

int com_getchar (void);

The com_getchar function reads a character from the serial input buffer.

The com_getchar function is part of RL-TCPnet. The prototype is defined in net_config.h.

note

• The serial driver functions must not use waiting loops because loops block the TCPnet system.
• You must provide the com_getchar function if the serial controller you use is different from the ones provided in the TCPnet source.

The com_getchar function returns the character value it read. It returns -1 if the input buffer is empty.

com_putchar, com_tx_active, init_serial

int com_getchar (void) {
  /* Read a byte from serial interface */
  struct buf_st *p = &rbuf;

  if (p->in == p->out) {
    /* Serial receive buffer is empty. */
    return (-1);
  }
  return (p->buf[p->out++]);
}