BRONKHORST®
Page 24
EL-FLOW
Base
Series Mass Flow Controllers
9.17.061
04, SLAVE DEVICE FAILURE, in case of writing to read-only register
04, SLAVE DEVICE FAILURE, in case of writing illegal value to register
When one of the written registers raises an exception, the value written to all subsequent registers are
discarded (ignored).
Diagnostics (08)
The following sub-functions are supported:
Sub-function code (dec)
Name
00
Return Query Data
10
Clear Counters and Diagnostics Register
11
Return Bus Message Count
12
Return Bus Communication Error Count
13
Return Bus Exception Error Count
14
Return Slave Message Count
15
Return Slave No Response Count
16
Return Slave NAK Count (always 0)
17
Return Slave Busy Count (always 0)
18
Return Bus Character Overrun Count
!
The maximum message size for the Return Query Data sub function is 100 bytes at 9600 baud (200
bytes at 19200 baud and 400 bytes at 38400 baud). When this size is exceeded, corrupted responses
may be received.
Possible exception responses:
01, ILLEGAL FUNCTION, in case of not-supported sub-function
03, ILLEGAL DATA VALUE, in case of an incorrect value for the data field
Report Slave ID (17)
The Slave ID field in the response is a string with the same contents as FlowDDE parameter 1 (indent
version nr/serial nr). The Run Indicator Status field in this message will indicate ON when the
device is in normal operating mode (FB_NORMAL).
Possible exception responses:
04, SLAVE DEVICE FAILURE, in case of an internal error
3.5.6 Available parameters
Modbus registers (in the data model) are numbered from 1 to 65536. In a Modbus PDU (Protocol Data
Unit) these registers are addressed from 0 to 65535.
The following table lists the most commonly used parameters.
MODBUS REGISTERS
PARAMETER
NAME
PARAMETER
TYPE
ACCES
S
PDU ADDRESS
REGISTER NUMBER
REMARK
Hex
Dec
Hex
Dec
Wink
Unsigned char
W
0x0000
0
0x0001
1
Value 14592
Initreset
Unsigned char
RW
0x000A
10
0x000B
11
Valve output
Unsigned int
RW
0x001F
31
0x0020
32
0..32767
Measure
Unsigned int
R
0x0020
32
0x0021
33
Setpoint
Unsigned int
RW
0x0021
33
0x0022
34
Setpoint slope
Unsigned int
RW
0x0022
34
0x0023
35
Analog input
Unsigned int
R
0x0023
35
0x0024
36
Control mode
Unsigned char
RW
0x0024
36
0x0025
37
Sensor type
Unsigned char
RW
0x002E
46
0x002F
47
Capacity unit index
Unsigned char
RW
0x002F
47
0x0030
48
Fluid number
Unsigned char
RW
0x0030
48
0x0031
49
Alarm info
Unsigned char
R
0x0034
52
0x0035
53
Temperature
Unsigned int
R
0x0427
1063
0x0428
1064
See addr 0xA138
Identification number
Unsigned char
RW
0x0E2C
3628
0x0E2D
3629
Normal step c. resp.
Unsigned char
RW
0x0E45
3653
0x0E46
3654
Stable situation c. resp.
Unsigned char
RW
0x0E51
3665
0x0E52
3666
