EDIT Device Control 1 (Ctrl-Q) This is one of four control codes meant to be used in controlling an auxiallary device.

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EDIT History On teletypes with paper tape punches, this control code turned on the paper tape punch and caused subsequent characters to be punched on the paper tape.

An older definition of this control code was XON (presumably Trasmit On). This was sent to a host device when the client device (such as a teletype) was ready to receive more characters. This second usage is the one that survived the transition to video terminals.

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EDIT Modern Usage In most command line line interfaces, this character exhibits the XON behavior. At least one terminal emulator program interprets this character as a DC1 command, causing subsequently received characters to be copied to a buffer.

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EDIT Suggested Implementation Any device receiving this control character should resume transmission of data, if such transmission was previously suspended.

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