Rockwell Automation ArmorStart Bulletin 280G, User Manual

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Explicit Messaging on DeviceNet™ 6-5
Sequence of Events
Use the following sequence of events as a guide for establishing
explicit messages in your SLC ladder logic.
1. Put the explicit message request data into an integer (N) file of the
SLC-500 processor.
2. Use the file copy instruction (COP) to copy the explicit message
request data entered in step 1 to the M0 File, words 224 through
256.
3. Use the examine-if-closed instruction (XIC) to monitor bit 15 of
the scanner’s module status register for an indication that it has
received a response from the ArmorStart.
4. Copy the data from the M1 file, words 224 through 256, into a file
in the SLC-500 processor using the file copy instruction (COP).
The following example shows the exact data format to perform a
“Get Attribute Single” request. This message will specifically access
parameter 104,
Average Current . The first three words are shown
segmented into two bytes, corresponding to the upper and lower bytes
shown in the explicit message request table (Table 6.4).
Note: The data in the table is shown in a hexadecimal format.
Therefore
parameter 104 decimal is equal to 68 hexadecimal
(0x68).
Table 6.7 Get_Attribute_Single Request
Table 6.8 Get_Attribute_Single Response
Figure 6.2 SLC Example of Ladder Logic Program
TXID Command Port Size Service MAC ID Class Instance Attribute
Word 0 1 2 3 4 5 6 7
N7:x 01 01 00 06 0E 04 000F 0068 0001 — —
TXID Status Port Size Service MAC ID Data
Word 10 11 12 13 14 15 16 17
N7:x 01 xx 00 06 0E 04 x — — — —