Technical Manual

East Wind Technologies, Inc.
Copyright © 2022 East Wind Technologies, Inc. All rights reserved. 11/59
1.9 Communication Protocol
1.9.1 Data sent format
Length
Command
Data
Checksum
 Length: 1 byte, number of bytes from Length byte to the last byte of Data.
 Command: 1 byte, Application-layer command, please refers to Application-layer
protocol in detailed.
 Data: length depends on the command type, from 0x00 to 0xFC bytes.
 Checksum: 1 byte, Exclusive OR (XOR) results from length byte to the last byte of
data.
1.9.2 Data returned format
 Success:
Length
Command
Data
Checksum
 Failure:
Length
Invert Command
Checksum
NOTE: "Failure" means that the communication between module and card failed.
1.10 Data Returned Time
Slaves begin to execute the command once received host's commands. The executive time is
normally less than 100ms, depand on the command type. Some command executive time maybe need
longer. The waiting time is decided by the card and the command type. So the hosts need to set the
waiting time according to the different commands.