STATYS
Jbus / Modbus serial link
8 OPMSTAJB0810-GB_01
IT
ALIANOENGLISH
7.
J
buS
/m
odbuS
p
rotocol
Reminder:
The JBUS/MODBUS protocol available on STATYS is slave and in RTU mode.
It uses the function 3 as ‘read registers’ and the function 6 as ‘write register’.
The slave number is set via the control panel or via the graphic touch screen.
Conventions:
The table addresses are written in hexadecimal, beginning with ‘0x’.
Some PLC systems request a relative address starting from 400 (0x0190) or 40001 (0x9C41), on this address
it’s necessary to add the first address of the JBUS/MODBUS table.
Frame errors management:
In case of wrong data request, the STATYS answers with the following frame error :
Error function code
Error code
Cause
80 + code function
1
Function error
80 + code function
2
Addresses error
80 + code function
3
Wrong data
80 + code function
6
busy
80 + code function
8
Write register error
8.
S
tatyS
J
buS
/m
odbuS
t
ableS
§
TABLE
Start addresses Table length in words JBUS/MODBUS FUNCTION
1
States
0x0140
4
3 READ
2
Alarms
0x0148
2
3 READ
3
Measurements
0x0220
64
3 READ
4
Permissions
0x0150
1
3 READ
5
Commands
0x0190
1
6 WRITE
8. 1.
H
ow
to
read
data
:
The identification, status and alarms tables should be read completely (this means the number of word to
read is equal to the table length).
The measurements table should be read word by word or per group, without exceed the length of the
table. (from 0x0220 to 0x025F).
8. 2.
I
ncomIng
data
Structure
:
Example of 6 words
1
2
3
4
5
6
7
8
9
10
11
12
MSB 0
LSB 0
MSB 1
LSB 1
MSB 2
LSB 2
MSB 3
LSB 3
MSB 4
LSB 4
MSB 5
LSB 5
WORD 0
WORD 1
WORD 2
WORD 3
WORD 4
WORD 5
b15 b0 b15 b0 b15 b0 b15 b0 b15 b0 b15 b0
S15 S00 S31 S16 S47 S32 S63 S48
A15 A00 A31 A16
M00
M01
M02
M03
M04
M05