Command Syntax

Commands must be sent to the CT-BOX in ASCII format. Each command is composed of a command field and zero, one or two parameter field(s), separated by a colon (: – 0x3A in hexadecimal notation). The number of parameter fields depends on the specific command.

Note

Commands are NOT case sensitive: they can be sent using uppercase or lowercase characters (conversion to uppercase is performed internally by the CT-BOX unit).

Each command must be terminated with a carriage return character \r (0x0D in hexadecimal notation, commonly known as CR).

Command example:

ACQ:ON\r

  • ACQ is the command field;

  • : is the parameter separation character;

  • ON is the first parameter field;

  • \r is the command termination character.

Commands are processed one at a time: the user must wait for a reply from the unit before sending the next command.

Replies

Replies from the CT-BOX are all formatted in upper case and are terminated with the carriage return / line feed sequence \r\n. The reply depends on the specific command; refer to the individual command sections for details.

Two specific replies are commonly used to indicate whether the command has been correctly processed:

  • ACKnowledge (ACK): the command is valid and has been correctly processed by the device.

    ACK\r\n

  • Not AcKnowledge (NAK): the command is either not valid, or it was not accepted by the device. The NAK reply is followed by an error code field that identifies the cause of the error (see the List of the Error Codes).

    NAK:2\r\n

    • NAK is the Not AcKnowledged response to an invalid command;

    • : is the parameter separation character;

    • 2 is a sample error code;

    • \r\n is the reply termination sequence.

Read Commands

Most commands support a read (query) form, obtained by sending ? as the last parameter field, e.g. MODE:?\r. The unit replies with the current value of the requested setting, terminated by \r\n.

Write Commands

Write commands carry the value(s) to be applied as parameter field(s), e.g. MODE:OSC\r, and are answered with ACK or NAK:x.

Each command description in this manual lists the exact command and reply formats in a dedicated Command Format table.