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Reference Manual
00809-0100-4832, Rev AA
October 2004
Rosemount 3095FC
3-22
Certain Opcodes only send data and do not receive data from the device. For
example, Opcode 8 requests the device to set the time and date. The device
resets the time and date and sends back an acknowledgement in which the
Opcode is repeated, but no data bytes are transmitted back. All
acknowledgements are 8-byte messages that repeat the Opcode received,
but do not transmit any data bytes.
Opcode 255 is an error message indicator. This is also an 8-byte message
with no data bytes included. The Opcode is set to 255 to indicate the
message received by the device had Cyclical Redundancy Error, but
contained invalid parameters. For example, if a request was made for the
information on Analog input #9, but the device only has 8 Analog inputs (0–7),
the device would respond back with the 8-byte message with the opcode
equal to 255 (error).
Opcode Table Configuration
Use the Opcode Table to group data for more efficient communication.
Parameters from different point types can be assigned to the Opcode table
data points, substantially reducing the number of polls from a host PC.
See Figure 3-16 on page 3-23
1. Select Configure > Opcode Table.
2. Select the Table Number for the Opcode Screen.
3. If the configuration has changed, update the version number. The
version number field attaches a version number to an Opcode table
configuration. It is a floating point number.
NOTE
Each Opcode Data point has a TLP box for mapping TLP values into the
Opcode Table Data point. If a host PC asks for a specific Opcode Data point,
the 3095FC returns the value that is referred by the mapped TLP.
Once the parameters have been configured in the Opcode Table:
1. Opcodes 10 and 11 can be used to read and write data directly
without specifying the Point Type, Logical Number, or Parameter
Number (TLP).
2. Opcodes 180 and 181 can be used to read and write the parameter
data and do not include the parameter definition.
162 Sets a single parameter
165 Set or send current configurable historical data
166 Set specified contiguous block of parameters
167 Send specified contiguous block of parameters
180 Send specified parameters
181 Set specified parameters
190/195 Reserved
224 Send Spontaneous Report-by-Exception (SRBX or RBX) message to host
225 Acknowledge Spontaneous Report-by-Exception message from device
255 Error messages transmitted by device in response to a request with invalid
parameters or format.
(1) Industry Canada
Opcode Description