ThingMagic Micro Hardware - Manual (Page 50)

Serial Communication Protocol
A D I V I S I O N O F T R I M B L E
Communication Protocol 45
Reader-to-Host Communication
The following diagram defines the format of the generic Response Packet sent from the
reader to the host. The Response Packet is different in format from the Request Packet.
CCITT CRC-16 Calculation
The same CRC calculation is performed on all serial communications between the host
and the reader. The CRC is calculated on the Data Length, Command, Status Word, and
Data bytes. The header is not included in the CRC.
Header Data Length Command Data CRC-16 Checksum
Hdr Len Cmd CRC HI CRC LO
1 byte 1 byte 1 byte 2 bytes
Status Word
Status Word
0 to 248 bytes 2 bytes