Samsung SP-M251 RS232C Command Table, Communication Format Complies with the RS232C Standard

5-2 RS232C Command Table

Communication Format (Complies with the RS232C Standard)

•Baud rate : 9,600 bps

•parity : None

•Data bits : 8, stop bit : 1

•Flow Control : None

Serial Communication Protocol

1.Command Packet Structure [7bytes]

0x08 0x22 cmd1 cmd2 cmd3 value CS

•A command packet consists of 7 bytes in total.

•The two bytes 0x08 and 0x22 signify that the packet is for serial communication.

•The following 4 bytes represent a pre-defined command that can be defined by the user.

•The last byte is the checksum which checks the validity of the current packet.

•Header [2 Byte]: Pre-defined values fixed to 0x08 and 0x22.

•Cmd1 [1 Byte]: The first value of the code defined in the command list (Hexadecimal)

•Cmd2 [1 Byte]: The second value of the code defined in the command list (Hexadecimal)

•Cmd3 [1 Byte]: The third value of the code defined in the command list (Hexadecimal)

•Value [1 Byte]: Input parameter for the command (Default: 0) (Hexadecimal)

•CS [1 Byte]: Checksum (the 2’s complement of the sum of all the values except for the CS value.)

2.Response Packet Structure [3 Bytes] 1. Success

0x03

0x0C

0xF1

2.Fail

0x030x0C0xFF

•When the received packet from an external device has a valid value, a Success packet is sent. Otherwise, a Fail packet is sent.

•A Fail packet is sent if:

•The received packet length is not equal to 7 bytes.

•The 2 byte packet header value is not equal to 0x08, 0x22.

•The check sum is incorrect.

•Failure detection by an external device

•An external device classifies the packet as Fail if it does not receive a Success packet within 100ms.

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