Delta Electronics manual Modbus CommunicationsASDA-B Series

Chapter 8 MODBUS CommunicationsASDA-B Series
int I;
outportb(PORT+MCR,0x08);	/* interrupt enable */
outportb(PORT+IER,0x01);	/* interrupt as data in */
outportb(PORT+LCR,( inportb(PORT+LCR) 0x80 ) );
/* the BRDL/BRDH can be access as LCR.b7 == 1 */
outportb(PORT+BRDL,12);
outportb(PORT+BRDH,0x00);
outportb(PORT+LCR,0x06);	/* set prorocol
	<7,E,1> = 1AH,	<7,O,1> = 0AH
	<8,N,2> = 07H	<8,E,1> = 1BH
	<8,O,1> = 0BH	*/
for( I = 0; I<=16; I++ ) {
while( !(inportb(PORT+LSR) & 0x20) ); /* wait until THR empty */
outportb(PORT+THR,tdat[I]);	/* send data to THR	*/
}
I = 0;
while( !kbhit() ) {
if( inportb(PORT+LSR)&0x01 ) {	/* b0==1, read data ready */

rdat[I++] = inportb(PORT+RDR); /* read data from RDR */

}

}

}

8-16 Revision January 2009