User Manual

3 - 2 MR400 RFID Reader Module, Integration Guide
For every request sent to the reader there may be one / more response packets that the reader sends back to
the host. A Typical Response Packet has been described in the following table:
Table 3-2
Field
Number of
Bytes
(Size)
Value Description
SOF 1 0x01 Described in Request Packet description.
Node Address 1 0~0x1F Described in Request Packet description.
Packet Length 1 See
Description
Described in Request Packet description.
Command
Mirror
1 See
Description
Mirror of the original command in the response packet.
Status 1 See
Description
The result or status of a command execution. See Status Field
Description section for more details.
Data Variable See
Description
In a typical response packet the size of data field may vary from 0
- to 250 bytes. The first byte of response data usually contains the
error code if error bit of status field has been set. For more
information on error bit see Status Field Description section. For
more information on error codes see Error Codes Described
section.
CRC 2 (1 for
LSB & 1
for MSB)
Dependent Bitwise inversion of the 16-bit CCITT-CRC of the packet
excluding SOF, with the LSB (Least Significant Byte) first.