User`s manual

DeviceNet (Master) Function
8-30
8
8-4 Explicit message function
When using only the I/O message function, there is no need to use the "explicit" message function.
The JW-32CUM1 can send a request for service to any device made by another manufacturer that uses
the Explicit message function defined in the DeviceNet specifications.
(Switch SW7-7 = ON - See page 8-9.)
This function uses the Explicit message data table (118 bytes each for request and response) in the JW-
32CUM1 (control section).
- An Explicit message data table request issues an Explicit message defined by DeviceNet, and asks any
corresponding device to provide service.
- The Explicit message data table response stores the service data details from the slave station.
Set the top address of the Explicit message table to the following point in system memory.
Addresses of the Explicit message table areas (requests and responses)
(O: Enable, -: Disable) *1: Specify the top address and select enabled or disabled.
(1) Details of the Explicit message table (requests)
JW-32CUM1 DeviceNet section reading flag, control section writing flag, and other parameters are
described.
Basic operation
mode
Table
No. of
bytes
Fixed Free
Master Slave
O—
Requests 118 39400 to 39565
#310 to #313 *1
Responses 118 39600 to 39765
Address * Parameter name Details
1st byte (39400)
DeviceNet section
reading flag
When the DeviceNet section of the JW-32CUM1 has
finished reading the contents being sent, the data in this
address is automatically inverted. (Inverting data changes
00
(H) to 01 (H) , and vise-versa.)
2nd byte (39401)
Control section
writing flag
When the data has been inverted, the host (control section
to DeviceNet section) will send a request message to the
slave station.
3rd byte (39402) Status The device status and response information are stored.
4th byte (39403) TXID (transaction ID) Assign an ID when creating a request.
5th byte (39404) Size Set the request data length.
6th byte (39405) Reserved area Use prohibited.
7th byte (39406) MAC ID Set a node address for the transaction object.
8th byte (39407) Service code Service code for the DeviceNet request.
9th byte (39410)
10th byte (39411)
Class ID Assign a class ID to the Explicit message sending target.
11th byte (39412)
12th byte (39413)
Instance ID
Assign an instance ID to the Explicit message sending
target.
13th byte (39414)
to
118th byte (39565)
Service data (106 bytes) Assign data that is defined by a service code.
*2: Addresses in parentheses are correct when the data table allocation system is set to "fixed
allocation."
- For details about the Explicit message parameters, see the "DeviceNet specifications."
To obtain a copy of "DeviceNet specifications," contact an ODVA branch office in your
country.