Rockwell Automation 57C442 Data Highway Plus Interface Module - Manual (Page 32)

4-14
05 REM The variables that follow define &
parameters for the &
GATEWAY CMD OK@ function
10 COMMON B3BASE% \! Represents the physical address of &
starting register on the Data Highway &
Plus module to be read from
20 LOCAL DST% \! The address of the bridge node on &
the local Data Highway Plus network
21 LOCAL STS% \! The location where the status &
resulting from the operation is stored
22 LOCAL SZE% \! The number of registers to be &
transferred
23 LOCAL CMD% \! The Data Highway Plus command &
sent by the module
30 DST% = 34
31 STS% = 0
32 SZE% = 100
33 CMD% = 3
40 IF NOT GATEWAY_CMD_OK@(STS%, CMD%, DST%,
&
“!01.24.00.00.84.00.80.00.00.14.00.00.N7:0”, &
VARPTR! (B3BASE%), SZE%) THEN 20000 \! process errors
In the example above, the routing bytes were determined as
follows.Recall that the last item in the actual ”slave_reg” parameter is
the destination file address.
Byte Value Meaning
1 LSAP 01 for a 1785-KA bridge
2 24h
3 DID_LO 00 for a 1785-KA bridge
4 DID_Hl 00 for a 1785-KA bridge
5 DNDE_LO 84h (see below)
6 DNDE_Hl 00 for a 1785-KA bridge
7 LIFETIME 80h for a1785-KA bridge
8 SID_LO 00 for a 1785-KA bridge
9 SID_HI 00 for a 1785-KA bridge
10 SNDE_HI
14h is the station number of the Data Highway
Plus module
11 SNDE_LO 00 for a 1785-KA bridge
12 NSAP 00 for a 1785-KA bridge