Omron CQM1H-SCB41 Communications Specifications, Transmission Procedure, Command Format

CompoWay/F Master ProtocolAppendix B

Communications Specifications

Item	Specification
Transmission path	Multipoint
connections
Communications	RS-232C, RS-422A/485, 4-wire half-duplex, 2-wire half-duplex
Synchronization	Start-stop
Baud rate	1,200/2,400/4,800/9,600/19,200 bps
	Default: 9,600 bps
Transmitted code	ASCII
Data length	7 bits or 8 bits (Default: 7 bits)
	Note: A 7-bit code is used with 0 added to the beginning.
Stop bits	1 bit or 2 bits (Default: 2 bits)
Error detection	Horizontal parity (none, even, or odd) (Default: Even)
	BCC (block check character)
	*1: Start-stop Sync Data Configuration for Protocol Macros
	LRC, 1 byte, equivalent to binary

Transmission Procedure

The PC or host computer serving as the master sends a command and the component serving as the slave returns a response for the command message contained in the command. One response message is returned for each command message. The movement of command and response messages is shown below.

Master (PC or host computer)

Slave (component)

Command message

Response message

Command and Response Formats

Note In the following diagrams “Hex” indicates hexadecimal values. Values in quotation marks, such as “00” indi- cate ASCII characters.

Command Format

	Node No.	Subaddress	Command	Text
		”00”	”0”	Data
1 byte	2 bytes	2 bytes	1 byte	1 byte	1 byte

Response Format

	Node No.	Subaddress	End code	Response	Text
		”00”	”00”		Data
1 byte	2 bytes	2 bytes	2 bytes		(See note.) 1 byte	1 byte

Note 1. Data is not saved in the response if there is a command frame error (i.e., if the end code is not 00 or 0F).

2. Other values are possible for the subaddress and SID.

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