Pulsar blackbox 134, Инструкция по эксплуатации

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Parameter Address
Data bits or data words exchange information between master and slave
devices. This data consists of parameters. All parameters communicated
between master and slaves have a 16-bit parameter address, which is
referred to as
Register Address .
The Modbus Register Address range is 100 to 999 according to parameter
list of P100-P999 on the ultrasonic level instruments. Accessible variables
are dependent upon the type of level instruments installed. For example, all
parameters related to flow will not be available for reading/writing if the
level instrument is a pump advanced unit. In this instance, accessing these
parameters will result in an error code 02 (data unavailable – refer to Error
Checking Section for more details).
Function Codes
Standard Modicon Modbus provides function codes from 1 to 247. Pulsar
Modbus protocols support function 1, 2, 3, 4, 6, 8 and 16.
Function Code Function Descriptions Data Type
01 read coil status bit mapped
02 read input status bit mapped
03 read holding register integer
04 read input register integer
05 Force single coil
06 write single register integer
08 diagnostic loop back none
16 write multiple registers integer
It is recommended that function code 03 or function code 04 is used for
reads and function code 06 is used for writes. This includes Boolean data.
Other codes are supplied for purposes of compatibility.
The level instruments will transmit error code if they receive a request
including an unsupported function code.