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RS-232 / IP Communication Protocol
CRC Calculation
CRC 0 = 0 (initial value)
CRC 1 = CRC_TABLE[CRC 0 ^ Byte 1] = CRC_TABLE[0x00 ^ 0x20] = 0x23
CRC 2 = CRC_TABLE[CRC 1 ^ Byte 2] = CRC_TABLE[0x23 ^ 0x01] = 0x0F
CRC 3 = CRC_TABLE[CRC 2 ^ Byte 3] = CRC_TABLE[0x9F ^ 0x06] = 0x8D
CRC 4 = CRC_TABLE[CRC 3 ^ Byte 4] = CRC_TABLE[0x8D ^ 0x03] = 0x93
Device ACK Packet: When the device receives supported commands from the host, it will respond with
the following ACK types:
Table
– ACK Type List
ACK Type
Byte 1
Byte 2
Byte 3
Byte 4
Last Byte
A
AB
CB
B
AB
LB
Index 1
Value 1
CB
ACK Type A (2 Bytes)
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
AB
ACC
0
0
Device ID (0x20)
CB
CRC
ACC: The devices acknowledge status. Accept or Reject.
1: Command is accepted (ACK).
2: Command is rejected (NAK).
Device ID: The HXL-
88’s ID is 0x20.
CB: Device always sends the CRC byte following the last byte.