Chapter 6. COMMREQ/Data_Init_Comm Programming
GFK-2892F
March 2019
63
COMMREQ #2: Read Configuration Command
The Read Configuration command is used to request configuration data from device on the Genius bus. It
causes the Gateway to send a Read Configuration datagram to the indicated device. After receiving the
request, the block returns its configuration data to the Gateway in 16-byte increments. When the Gateway has
received all the configuration data, it transfers that complete data image to the PNC, which then transfers the
data to the deposit memory location specified in the Command Block. Because configuration data consists of
both bit-type and byte-type portions, it is best to place it in word memory, then move the bit-oriented data to
bit memory. Contents of Read Configuration Reply messages for I/O blocks are shown in the
Genius I/O System
and Communications
User’s Manual
,
GEK-90486-1
.
The VersaMax I/O Station (GNIU) does not support this COMMREQ. Use PME
to read the GNIU’s configuration
data.
Command Block for the Read Configuration Command
Address
Command Length
7
A1
No Wait
0
A2
Status Block memory type
70 (%I), 72 (%Q), 8 (%R), 10 (%AI), 12 (%AQ) or 196 (%W)
A3
Status Block offset
Beginning address for the COMMREQ Status Block.
A4
Idle timeout value
0
A5
Max. communications time
0
A6
Command number
2
A7
PROFINET Device number
1-255: The device number of the targeted GCG Genius Gateway.
A8
Genius Device Number
1-29: the SBA of the targeted Genius Device.
A9
Maximum data memory
length. May represent either
bits or words (depends on
the memory type selected
below).
18 words (288 bits): any discrete block
13 words (208 bits): 16-Circuit AC Input block
42 words (672 bits): Analog blocks (4-in/2-out)
42 words (672 bits): RTD or Thermocouple block
44 words (704 bits): 6-Input Analog blocks
42 words (672 bits): 6-Output Analog blocks
35 words (560 bits): High-Speed Counter
If the length of data returned by the device exceeds the length specified
here, the GCG writes as much data as possible to the PLC CPU Memory
and returns a data error to the COMMREQ Status Block. The GCG will not
write past the computed end-point.
If the same COMMREQ will be used to read configuration data from more
than one type of block (for example, in a subroutine), be sure to allow
enough length to accommodate the largest amount of data that might be
returned.
A10
Deposit Memory type
Enter the code representing the CPU Memory Type where the GCG will
deposit the data obtained from the target Genius Device. Use the same
codes as in 2.
A11
A12
Memory offset
bytes 1, 2
bytes 3 ,4
Starting address within the Deposit Memory type.
(Byte 4 is MSB, Byte 1 is LSB)
