Mocomtech CRS-300 Packet Structure, Start of Packet, Target Address, Delimiter, Qualifier

CRS-300 1:10 Redundancy Switch	Revision 16
Remote Control	MN/CRS300.IOM

oTo a local BUC or transceiver connected to a local modem;

oTo a distant end BUC or transceiver through the distant end modem.

C.5 Packet Structure

Controller-to-Target

	Start of	Target		Address	Instruction	Code	Optional	End of Packet
	Packet	Address		Delimiter	Code	Qualifier	Arguments
<			/			= or ?		Carriage Return
	ASCII code 60			ASCII code 47		ASCII codes		ASCII code 13
						61 or 63
	(1 character)	(4 characters)		(1 character)	(3 characters)	(1 character)	(n characters)	(1 character)
	Example: <0000/RSH=30[cr]

Target-to-Controller

	Start of	Target		Address	Instruction	Code	Optional		End of Packet
	Packet	Address		Delimiter	Code	Qualifier	Arguments
>			/			=, ?, !, or *			Carriage Return,
	ASCII code 62			ASCII code 47		ASCII codes			Line Feed
						61,63,33 or 42	(From 0 to n		ASCII codes
	(1 character)	(4 characters)		(1 character)	(3 characters)			13,10
						(1 character)	characters)		(2 characters)

Example: >0000/BBU=107[cr][lf]

C.5.1 Start of Packet

Controller-to-Target:This is the character '<' (ASCII code 60)

Target-to-Controller:This is the character '>' (ASCII code 62)

Because this is used to provide a reliable indication of the start of packet, these two characters may not appear anywhere else within the body of the message.

C.5.2 Target Address

While up to 9,999 devices can be uniquely addressed, connection to the CRS-300 imposes some basic limitations:

•In EIA-232applications, the Switch address is fixed at 0000.

•In EIA-485applications, the Switch may be set to an address of 1000, 3000, 5000 or 7000. This allows up to four Switches to be connected on the same bus.

•The 11 modems that may be connected to the Switch may be accessed for remote monitor & control through the Switch via virtual addresses. The details of this addressing scheme is shown in Appendix B. ADDRESSING SCHEME INFORMATION. Valid remote commands and queries that can be sent to the modems via the Switch depend upon the

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