Rockwell Automation 6001-F2E AB STANDARD DRIVER SFTW - Manual (Page 26)

Application Program Examples
Appendix A
A-4
/* ––––––––––––––––––––––––––––––––––––––––––––––––––– */
/*
DH/DH+ Application Library (c) 1989 Allen–Bradley
APPLICATION: PLC–2 Unprotected Read
SYMBOL: PLC2_URD
Include files:
Linkable Driver:
#include “krdefs.h”
#include “stddrv.h”
Application Variables:
int size,
PLC_FCT;
d_buff[...]
unsigned int status,
io_stat[2],
dt_addr = 0110,
timeout;
char device[]= “KR:0”;
unsigned char destination;
struct SD_FB DHP_MSG;
*/
/* Initialize the DH-485 function block */
DHP_MSG.dev = device; /* Communication device */
DHP_MSG.stat = &io_stat[0]; /* I/O status */
DHP_MSG.L_R = 0;
DHP_MSG.dst = &destination; /* DH-485 address */
DHP_MSG.dta = &dt_addr; /* DT address(byte location) */
DHP_MSG.len = size; /* Size in bytes (max 244) */
DHP_MSG.buf = &d_buff[0]; /* Read buffer */
DHP_MSG.TO = timeout; /* Reply timeout in sec */
PLC_FCT = PLC2_URD; /* Initialize a PLC function */
PLC-2 Unprotected Read