If the
Telegram-Info-Byte
is 04h, an additional offset is entered. Otherwise there is no
Offset in the telegram. Calculating the Offset with fragmented transfer:
Data_Offset = (Fragment_c 1) × (IO_Size-1) -7 + Offset
n
Data_Offset:
–
Offset of the data in the input area
n
Fragment_counter:
–
Absolute number of fragments
n
IO_Size:
–
Number of used bytes in the address area
n
Offset:
–
Offset value in the telegram
Here the received user data of the serial communication may be found.
Bit 3...0
Reserved for sending
Bit 7...4
n
8h: Acknowledgement: Idle state
n
Ah: Acknowledgement: input area free for new data
n
Bh: Command: Execute a reset on the CP
4.3.3 Examples
IO-Size = 60byte, length = 40byte
Host system
CP
Byte
Function
Byte
Function
0
0Ah Command
u
1
00h Telegram-Info
2
00h Length high byte
3
28h Length low byte
4...43
User data byte 0...39
44...59
is not used
t
0
A0h Acknowledgement
IO-Size = 16byte, length = 50byte
Header Host system
CP
Byte
Function
Byte
Function
0
09h Command
u
1
00h Telegram-Info
2
00h Length high byte
3
28h Length low byte
Offset
User data
Acknowledgement
Send data without frag-
mentation
Send data with fragmenta-
tion
VIPA System SLIO
Deployment
Principal communication via back plane bus > Examples
HB300 | CP | 040-1CA00 | en | 18-28
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