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Cypress SIO-7300 - Packet Structure
The SIO-7300 accepts one TCP connection at a time on port 10001. The host software sends binary encoded data to
the SIO-7300. If the data was formatted properly, the SIO-7300 will respond accordingly. If the SIO-7300 did not
receive correctly formatted data, it will not respond.
The SIO-7300 protocol consists of commands and responses, which share a common format. If any of the fields are
incorrect or invalid, the device does not respond.
[sync][length][source][destination][type][response][command][status][data][checksum]
Field Name
Field Length
Field Description
Sync
3 bytes
0x000000. Used to signify the beginning of a packet.
Length
1 byte
The length of the packet, starting from Length (excluding Sync).
Source
1 byte
The address of the device from which this packet originated. This begins with 0x01
plus the address of any expansion devices. The host’s address is 0xF1.
Destination
1 byte
The address of the devices to which this packet is being sent.
Type
1 byte
Set depending on the device that created the message. If the host device (network
controller) created the message, it is 0xF1; otherwise it is 0x01.
Response
1 byte
Constant value of 0x06.
Command
1 byte
Constant value of 0x00
Status
1 byte
The command/response codes. This primarily controls the size and contents of the
Data field. If an invalid status value is received, the SIO-7300 will use the default
NoData status, this does not return a reply.
Data
2-32 bytes
Depending on the Status, this filed may contain I/O data or reader data. See the
tables below for more information.
Checksum
1 byte
The sum of all data in the packet before the Checksum Field, modulo 0x100 (masked
to one byte).