COMMERCIAL IN CONFIDENCE
Page 10
1. Write the
security byte
with value 5
(9500 — Not Required)
2. Send message number 5 (enter program mode)
3. Send messages as required to change desired parameters
4. Write the
security byte
with value 6
(9500 — Not Required)
5. Send message number 6 (exit program mode)
It is possible to write to parameters without using this sequence, but the unit will simply
hold new values in the menu structure, and will not apply the new values to the
process control variables. However, if new parameters are uploaded and then the
menu entered from the front panel, any uploaded parameters will be effective on
leaving the menu. When using communications t
he
enter program mode / exit
program mode
message sequence must be sent to cause any new values to be
applied to the controller.
2.3.1
Enter Program Mode
Byte No
Meaning
Value
1
Slave address
xx
2
ModBus Function code (write register)
06
3
Security message function marker (1=security, 5=function 5)
15
4
not used (any value may be sent)
xx
5
not used (any value may be sent)
xx
6
not used (any value may be sent)
xx
7
CRC lo byte
??
8
CRC hi byte
??
The
security byte
must be set to 5 prior to this message
(not required for 9500)
. If the
instrument is successfully set into
remote program mode
, and the keyboard is
successfully locked, the response will be the same as the message. If the instrument
is currently in manual menu entry mode, an error response code 6 (device busy) will
be returned. This command may be repeated while already in
remote program mode
with no ill effect.
2.3.2
Exit Program Mode
Byte No
Meaning
Value
1
Slave address
xx
2
ModBus Function code (write register)
06
3
Security message function marker (1=security, 6=function 6)
16
4
not used (any value may be sent)
xx
5
not used (any value may be sent)
xx
6
not used (any value may be sent)
xx
7
CRC lo byte
??
8
CRC hi byte
??
The
security byte
must be set to 6 prior to this message
(not required for 9500)
. The response will be
the same as the message if the instrument is currently in
remote program mode
, and a restart will be
initiated, otherwise an error response code 1 (illegal function) will be returned.