LightSpeed Technologies CAT 860 user manual Control Character Hex Value and Definition

5. Warranty, Safety	& Specifications
4. Troubleshooting
3. Optional	Accessories
2. Setup & Use
1. Overview

13.RS-232 SERIAL INTERFACE PROGRAMMING CONT’D

Control Character Hex Value and Definition

STX	(0x02)	Start character of an action command packet.
EOT	(0x04)	End character of any command packet.
ACK	(0x06)	Only response character from the CAT 860
		if action command (PING command only) is
		properly received and accepted.
NACK	(0x15)	Only response character from the CAT 860 if
		any command is corrupted or unsupported.
		The CAT 860 should send a NACK if:
		1. The CAT 860 can not recognize the start or
		command characters.
		2. The CAT 860 does not receive an end
		character after receiving a total of twenty
		characters after receiving valid start and
		command characters.
		3. The CAT 860 does not receive an end
		character after waiting 50ms after receiving
		valid start and command characters.
CMD	(find hex value	This is the general symbol for the command
	from Table 1)	character derived from Table 1.
Param	(find hex value	This is the general symbol for the parameter
	from Table 1)	character(s) associated with the command
		character. They are derived form Table 1.

General Format for Action Command Exchange for Basic and Advanced Command Set:

In this example, the serial controller sends an action command packet to the CAT 860 and in response the CAT 860 repeats back the action command packet the serial controller. The <Param> characters can be absent from the action command packet, but all response packets will have one or two added <Param> characters containing the values of the pertinent internal CAT 860 register.

Controller: <STX><CMD><Param><EOT>

CAT 860: <STX><CMD><Param><EOT>

13.RS-232 SERIAL INTERFACE PROGRAMMING CONT’D

General Format for Query Command Exchange:

In this example the external controller sends query command packet to CAT

860.CAT 860 repeats back the action command packet in response which also includes one or two imbedded <Param> characters. The <Param> characters which are added to the query command packets contain the values of the perti- nent internal CAT 860 registers.

Controller: <STX><CMD><EOT>

CAT 860: <STX><CMD><Param><Param><EOT>

General Format for Aborted Command Exchange (Both Basic and Advanced Command Sets:

In this example the external controller sends either an action or query command to CAT 860 and the command is either corrupted or unsupported. The <Param> characters can be absent.

Controller:	<STX><CMD><Param><EOT>
CAT 860:	<NACK>

Note: It is expected that each button press from the serial controller would use only a single command/query packet. If a single button press must issue a string of multiple command/query packets then each packet must be separated by at least a 10ms delay, or alternately, a new packet must wait until the CAT 860 issues a response packet/character before it can be sent.

5. Warranty, Safety	& Specifications
4. Troubleshooting
3. Optional	Accessories
2. Setup & Use
1. Overview

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