Burkert Type 8644 - Manual (Page 59)

8644/phoenix - 55
S
YSTEM
D
ESCRIPTION
• Start fragment
Bit 7 0= Request
1= Response
Bit 6:5 Identification 00: Start fragment
Bit 4 0: not fragmented
1: fragmented
Bit 3:0 service 0: no action
1: Read_PCP
2: Write_PCP
3: Read
4: Write
5: Read PDU length (data width of the VC1 channel)
• Continuation fragment
Bit 7 0 = Request
1 = Response
Bit 6:5 Identification 01: Continuation fragment
Bit 4:0 Count 1 – 0x1F continuation number; after 0x1F comes 0
• Conclusion fragment
Bit 7 0 = Request
1 = Response
Bit 6:5 Identification 10: Last fragment
Bit 4:0 reserve
• Cancel / Error fragment (concerning error display)
Bit 7 0 = Request
1 = Response
Bit 6:5 Identification 11: Cancel / Error fragment
Bit 4:0 number of valid bytes follow
Data block
The construction of the data block corresponds to that during DPV1 accesses.
Byte 1: Number of data bytes
Byte 2 up to number of data bytes +1: Data
• Start fragment
Byte 1: Service
Byte 2: Module number
Byte 3: Index high
Byte 4: Index low
Byte 5: Sub-index
Byte 6: Length
Byte 7: Data block, if required
…
Byte n: Data block, if required