uart.zip_30F6014_it

// this program is a test for uart1 // // fosc/4 = FCY // // baud rate = FCY/(16*(BRG+1)) // #include "p30f6014.h" unsigned char k,tr_cnt,tr_no,buf[20]; unsigned BUF_EMPTY,rec; void init_uart1(void); int main (void) { init_uart1(); rec = 0; do{ for(k=0;k<20;k++) buf[k] = k; tr_no = 20; tr_cnt = 0; BUF_EMPTY = 0; if(rec == 1){ rec = 0; do{ if (!U1STAbits.UTXBF){IEC0bits.U1TXIE=1;IFS0bits.U1TXIF = 1;} }while(!BUF_EMPTY); } }while(1); return 0; } void init_uart1(void){ U1MODEbits.UARTEN = 1; /* enable the uart */ U1STAbits.UTXEN = 1; /* enable a transmission */ IFS0bits.U1TXIF = 0; /* clear interrupt flag */ IEC0bits.U1TXIE = 1; /* enable interrupts */ IFS0bits.U1RXIF = 0; /* clear interrupt flag */ IEC0bits.U1RXIE = 1; /* enable interrupts */ U1BRG = 31; /* baud rate = 19200 for fosc = 40 MHz */ } void __attribute__((__interrupt__, __shadow__)) _U1TXInterrupt(void) { IEC0bits.U1TXIE =0; if(tr_cnt < tr_no){ U1TXREG = buf[tr_cnt]; tr_cnt++; } else{ BUF_EMPTY = 1; } IFS0bits.U1TXIF = 0; /* clear interrupt flag */ return; } void __attribute__((__interrupt__, __shadow__)) _U1RXInterrupt(void) { buf[tr_cnt]= U1RXREG; rec = 1; IFS0bits.U1RXIF = 0; /* clear interrupt flag */ return; }