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It's recommended that the matching resistance shall be added between the foremost and instruments
A, B and the rated resistance range is 120Ω~10 kΩ.
Wiring for other settings:
7.1Transmission mode
The information is transmitted asynchronous and in bytes,and the communication information transmitted between
the host and the slave is in a 10-bit word format, including 1 start bit,8 data bits(the smallest valid bit is sent first),no
parity check bit.1 stop bit,set to parity bit or 2 bit stop bit,11 bit word format.
7.2Information frame format
Address
Code
Function
Code
Data
Field
CRC check code
1 byte
1 byte
N bytes
2 bytes
Address code:the address code is at the beginning of the frame and consists of one byte(8 bit
binary code).The decimal bit is 0-255.Only 1-247 is used in the PZ instrument,and the other addresses
are reserved.These bits indicate the sddress of the user-specified terminal device,which will
receive data from the host connected to it.The address of each terminal device must be unique,and
only the addressed terminal will respond to a query containing that addresss.When the terminal sends
back a response,the slave sddress data in the response tells the host which terminal is communication
with it.
Function code:the function code tells the addressable terminal what function to perform,The
following table lists the functional codes used in this series of instruments,as well as their
significance and functions.
Dunction
Definition
Operate
03H/04H
Read data registe
Get the current binary value of one or more registers
10H
Preset multi-registe
Set binary values into a series of multiple registers
Data area:the data area contains the data needed by the terminal to perform a specific function
or the data collected by the terminal in response to the query.The content of this data may be a
Two-core
shielded
line/shielding
layer is connected with ground.