Bronkhorst Modbus slave interface - Manual (Page 20)

BRONKHORST ®
Details and meaning can be found in document 9.17.023 Operation instructions digital instruments.
This document can be found at:
http://www.bronkhorst.com/en/downloads/instruction_manuals/
• Access indicates whether parameter can be Read and/or Written.
• When a byte parameter is read, the upper 8-bits of the Modbus register will be 0. When a byte
parameter is written, the upper 8-bits must be set to 0.
• Long integer parameters have a length of 4 bytes and are mapped on two consecutive Modbus
registers. The first register contains bit 32-16, the second register contains bit 15-0.
• Floating point parameters have a length of 4 bytes and are mapped on two consecutive Modbus
registers. Floats are in single precision IEEE format (1 sign bit, 8 bits exponent and 23 bits fraction).
The first register contains bit 32-16, the second register contains bit 15-0.
• String parameters can have a length of maximal 16 bytes and can take up to 8 Modbus registers
where each register contains two characters (bytes). The upper byte of the first register contains
the first character of the string. When writing strings, the write action should always start from the
first register as a complete block (it is not possible to write a part of a string). If the string is shorter
than the specified maximum length the string should be terminated with an 0.
• Parameters Temperature, Counter value and Counter limit can be found in the parameter table as
an unsigned integer variant and as a floating point variant. Only the floating point variant supports
the full parameter range and resolution.
MODBUS REGISTERS
PARAMETER NAME PARAMETER
TYPE
ACCESS
PDU ADDRESS REGISTER NUMBER
REMARK
Hex Dec Hex Dec
Usertag String (13 bytes) RW 0xF130..0xF136 61744..61750 0xF131..0xF137 61745..61751
PID-Kp Float RW  0xF2A8..0xF2A9 62120..62121 0xF2A9..0xF2AA 62121..62122
PID-Ti Float RW  0xF2B0..0xF2B1 62128..62129 0xF2B1..0xF2B2 62129..62130
PID-Td Float RW  0xF2B8..0xF2B9 62136..62137 0xF2B9..0xF2BA 62137..62138
Density actual Float R 0xF478..0xF479 62584..62585 0xF479..0xF47A 62585..62586
Dynamic display factor Float RW  0xF508..0xF509 62728..62729 0xF509..0xF50A 62729..62730
Static display factor Float RW  0xF510..0xF511 62736..62737 0xF511..0xF512 62737..62738
Exponential smoothing Float RW  0xF520..0xF521 62752..62753 0xF521..0xF522 62753..62754
Modbus baudrate Long integer RW  0xFD48..0xFD49 64840..64841 0xFD49..0xFD4A 64841..64842
Page 20 Modbus interface 9.17.035