101
12
Interface
101
Interface
Chapter
12
17 (0x0011) Return Slave Busy Count
(no count-up for the F325)
Slave busy counts issued by a slave device are returned.
18 (0x0012) Return Bus Character Overrun Count
(no count-up for the F325)
The number of times character overrun errors of the frame that matched the slave address is read.
20 (0x0014) Clear Overrun Counter and Flag
The overrun counter, and drops the error flag are cleared.
■
Regarding error response
The slave device returns an error response without executing the command when a request from the
master contains a failure. 0x80 is added to the requested function code.
Exception code is judged after the received frame.
The priority of the exception code judgment is 1
→
3
→
2.
[Request]
Function
1 byte
0x08
Sub-function
2 byte
0x00, 0x11
Data
2 byte
0x00, 0x00
[Response]
Function
1 byte
0x08
Sub-function
2 byte
0x00, 0x11
Data
2 byte
Busy
[Request]
Function
1 byte
0x08
Sub-function
2 byte
0x00, 0x12
Data
2 byte
0x00, 0x00
[Response]
Function
1 byte
0x08
Sub-function
2 byte
0x00, 0x12
Data
2 byte
Character, Overrun, Count
[Request]
Function
1 byte
0x08
Sub-function
2 byte
0x00, 0x14
Data
N x 2 bytes
0x00, 0x00
[Response]
Request echo
Exception code No.
1
Function code error
2
Address out of range error
3
Data value error