LubriMist
®
Model JD
Oil Mist Generating System
Installation and Operating Manual
Page 87 of 152
Holding Register
Function Code 03, Refers to the setpoints of the JD
For a description of the holding registers refer to (Holding Register Addresses) below.
Message frame being sent
[01] [03] [00] [00] [00] [01] [84] [0a]
1) Device I.D. in
Modscan screen has to
be the same as the JD
location
2) In the Modscan
screen Modbus point
type & Function code are
the same thing
3) Data sent out,
consisting of address
(hex) and length
4) Cyclical Redundancy
Checking or CRC
[01]
[03]
([00] [00]) ([00][01])
[84] [0a]
The first two sets of numbers are the same as the previous.
1) Is the device ID 01.
2) The Function code 03.
3) Data sent---will consist of 2 sets of data ([00] [00]), ([00] [01]), the first two sets of numbers
[00], [00] are the address (hex). To poll a single value, type in the address in the Modscan screen
address (hex) box.
See Holding Register addresses below.
The second set of numbers [00], [01] are the (length). In Function Code (03) the length can have up
to 24 polling places, which will give a hex value of [18], in the sent message frame.
Note: In order to poll all 24 Holding Register Address values, the length has to be set at 24 and the
Address (HEX) has to be set a 1.
The Holding Register Addresses can only be polled in consecutive order. Meaning either from the
beginning of the string, anywhere in the middle or the end of the string can be polled. Trying to poll
random Holding Register Addresses cannot be done. Example; (02 air temp., 07 supply air press.,
09 reg. air press.), cannot be polled as a string.
2) Cyclical Redundancy Check--- CRC, is a number assigned by the computer and cannot be changed by
the user.
Function code 03—in Modscan screen the combined address HEX and the length cannot exceed 25
Or an error will occur in the receiving information in the form of ([01] [83] [00] [41] [30]), the [83] being the
error code.