Chapter 6. Serial I/O, SNP & RTU Protocols
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PACSystems* RX7i, RX3i and RSTi-EP CPU Reference Manual
GFK-2222AD
Response:
The normal response contains the data from the group of registers that were read. The Byte Count field
specifies the quantity of bytes to follow in the Read Data field.
Here is an example of a response to the query:
Field Name
Example
(Hex)
Slave Address
11
Function
17
Byte Count
0C
Read Data 1 Hi
00
Read Data 1 Lo
FE
Read Data 2 Hi
0A
Read Data 2 Lo
CD
Read Data 3 Hi
00
Read Data 3 Lo
01
Read Data 4 Hi
00
Read Data 4 Lo
03
Read Data 5 Hi
00
Read Data 5 Lo
0D
Read Data 6 Hi
00
Read Data 6 Lo
FF
Error Check (LRC or CRC)
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