Endress+Hauser EngyVolt RV12, Руководство по эксплуатации

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EngyVolt RV12 Appendix
45
Error check (Hi):
The top (most significant) eight bits of a 16-bit number representing the error check value.
Response
The example illustrates the normal response to a request for a single floating point
parameter i.e. two 16-bit Modbus Protocol Registers.
First Byte Last Byte
"Slave" Function
code Byte
count First
register
(Hi) First
register
(Lo) Second
register
(Hi) Second
register
(Lo) Error check
(Lo) Error
check (Hi)
"Slave" address:
8-bit value representing the address of slave that is responding.
Function code:
8-bit value which, when a copy of the function code in the query, indicates that the slave
recognized the query and has responded. (See also Exception Response (→  46)).
Byte count:
8-bit value indicating the number of data bytes contained within this response
First register (Hi)
2)
:
The top (most significant) eight bits of a 16-bit number representing the first register
requested in the query.
First register (Lo)
2)
:
The bottom (least significant) eight bits of a 16-bit number representing the first register
requested in the query.
Second register (Hi)
2)
:
The top (most significant) eight bits of a 16-bit number representing the second register
requested in the query.
Second register (Lo)
2)
:
The bottom (least significant) eight bits of a 16-bit number representing the second
register requested in the query.
Error check (Lo):
The bottom (least significant) eight bits of a 16-bit number representing the error check
value.
Error check (Hi)
2)
:
The top (most significant) eight bits of a 16-bit number representing the error check value.
2) Together, these four bytes represent the value of the floating point parameter requested in the query.