/* //////////////////////////////////////////////////////////////////////////// Names for Numbers //////////////////////////////////////////////////////////////////////////// */ #define RX_BUFF_SIZE 10 /* Must be less than 256 */ /* //////////////////////////////////////////////////////////////////////////// Module Variables //////////////////////////////////////////////////////////////////////////// */ char rx_buff[RX_BUFF_SIZE]; /* Circular UART receive buffer */ unsigned char rx_in; /* Next emtpy spot in rx_buff[] */ unsigned char rx_out; /* Oldest byte in rx_buff[] */ /* //////////////////////////////////////////////////////////////////////////// serial_handler() /////////////////////////////////////////////////////////////////////////////// DESCRIPTION: This is the interrupt handler for the on-board serial port. REVISIONS: 19 APR 98 - RAC - Lifted from the DART II Code //////////////////////////////////////////////////////////////////////////// */ interrupt [0x23] void serial_handler() { if (RI0) { /* It's a receive interrupt */ RI0 = 0; /* Clear the interrupt */ rx_buff[rx_in++] = SBUF0; /* Put new byte in buffer */ if (rx_in == RX_BUFF_SIZE) { /* Just reached buffer end */ rx_in = 0; /* Wrap to the beginning */ } /* End 'reached buffer end' */ } /* End 'receive interrupt' */ } /* End serial_handler() */ /* //////////////////////////////////////////////////////////////////////////// kbhit() getch() /////////////////////////////////////////////////////////////////////////////// DESCRIPTION: kbhit() indicates whether or not unread data has accumulated in the serial input buffer. getch() waits for such data and returns the oldest character in the buffer. REVISIONS: 19 APR 98 - RAC - Adapted from the DART II code. //////////////////////////////////////////////////////////////////////////// */ char kbhit() { /* The buffer contains data */ return (rx_in != rx_out); /* if the in and out */ } /* indexes are different */ /* ///////////////////////////////////////////////////////////////////////// */ char getch() { char rv; /* Put return character here */ while (!kbhit()) ; /* Wait for a character */ rv = rx_buff[rx_out++]; /* Grab byte from rx buffer */ if (rx_out == RX_BUFF_SIZE) { /* Just reached buffer end */ rx_out = 0; /* Wrap to the beginning */ } /* End 'reached buffer end' */ return rv; /* The answer */ } /* End getch() */