Allen-Bradley Compact I/O 1769-ADN DeviceNet, Руководство пользователя

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Publication 1769-UM001B-EN-P - October 2002
B-18 Explicit Messaging Application Examples
The actual status word in the reply, i.e., the fourth word of the reply,
is defined as follows:
Refer to the Troubleshooting information in Chapter 4 for additional
information on Recoverable and Unrecoverable, Major and Minor
faults.
Get 1769 I/O Module Status
The Get 1769 I/O Module Status command has 6 words, where the
first three are required by the 1747-SDN and the last three are sent to
the 1769-ADN and the specified 1769 I/O module. As you will see in
the sample ladder logic below, a command is sent to the 1747-SDN
via a COPy instruction to the scanner’s M0 file.
The reply is then received in the scanner’s M1 file. The user program
is notified that the command reply is ready when the scanner sets an
input image bit (I:s/15, where s is the slot number of the 1747-SDN).
When this bit is set, the user program COPies the reply from the
scanner’s M1 file.
Following each command reply, the user program must MOVe a
command value of 4 hexadecimal to the appropriate M0 file word to
clear the previous reply from its buffer, making it ready for the next
command.
Bit Description
0 When true, indicates the device has an owner
1 Reserved, set to 0
2 When true, indicates the application of the devices has been configured
beyond out-of-the-box defaults
3 Reserved, set to 0
4-7 Vendor specific
8 When true, indicates the device has experienced a Minor Recoverable Fault
9 When true, indicates the device has experienced a Minor Unrecoverable Fault
10 When true, indicates the device has experienced a Major Recoverable Fault
11 When true, indicates the device has experienced a Major Unrecoverable Fault
12-15 Reserved, set to 0