Rev. 06
86/99
9.1.
ModBus packaged format
CUSTOMER
ADDRESS
1 byte
Each device on a communication bus must have a unique address,
otherwise two different units could reply simultaneously to the same
request. All ports of the relay will use this address which can be set
a value between 1 and 247. When the master transmits a frame
with the slave address to 0 indicates a Broadcast. All the slaves in
the communications bus will carry out the requested action, but no
one will reply to the master. The Broadcast will only be accepted to
write, as it makes no sense to make a read request in the
Broadcast, as no one will reply this request.
FUNCTION CODE
1 byte
This is one of the function codes supported by the equipment. In
this case, the only function codes supported are 3 to read and 16 to
write. When the slave has to reply with an exception one of these
frames, it is indicated by putting 1 in the most important bit of the
correspondent function. Thus, an exception for the function 3 will be
indicated with a 83 as a function code; and an exception for the
function code 16 or 0x10 in hexadecimal, will be indicated with an
0x90.
DATA
N bytes
This part consists of a variable number of bytes, depending on the
function code. It may include: addresses, data lengths, settings,
commands or exception codes sent by the user.
CRC
2 bytes
Control code of two bytes. The ModBus/RTU includes a 16 bit CRC
in each frame, to detect errors. If the slave detects an erroneous
frame, based on a CRC that is not correct, it won’t take any action,
nor will reply anything to the master. The management of the CRC
is LSB-MSB.
DEAD TIME
Necessary
time
to
transmit 3,5
Bytes
A frame is terminated when nothing is received for a period of 3,5
bytes. It means:
15 ms at 2400 bps
2 ms at 19200 bps
...etc.
9.2.
Function codes
HEX
DEC
CODE
MODBUS
NAME
DEFINITION
COMMENT
0x03
3
Read
Holding
Registers
Reading
of
Any Value
This function allows the master to read 1 or more
consecutive addresses of a relay. The registers always are
of 16 bits, with the most important byte at first. The
maximum number of registers to be read in a package is
60.
0x10
16
Preset
Multiple
Registers
Script
This function allows writing one or more registers that
represent one or more settings. The registers are values of
2 bytes of length, transmitted with the most important byte
at first. The maximum number of register to be written in a
package is 60.
Summary of Contents for SIA B
Page 7: ...www fanox com Rev 06 7 99 2 DIMENSIONS AND CONNECTION DIAGRAMS 2 1 Frontal view...
Page 8: ...www fanox com Rev 06 8 99 2 2 Case dimensions The dimensions are in mm Cut out pattern...
Page 9: ...www fanox com Rev 06 9 99 2 3 Connection diagram NOTE STRIKER 6 24 Vdc 0 1 W s...
Page 18: ...www fanox com Rev 06 18 99 Dimensions...
Page 28: ...www fanox com Rev 06 28 99...
Page 29: ...www fanox com Rev 06 29 99...
Page 30: ...www fanox com Rev 06 30 99...
Page 31: ...www fanox com Rev 06 31 99...
Page 33: ...www fanox com Rev 06 33 99...
Page 34: ...www fanox com Rev 06 34 99...
Page 35: ...www fanox com Rev 06 35 99...
Page 98: ...www fanox com Rev 06 98 99 NOTES...
Page 99: ...www fanox com Rev 06 99 99...
