Tally Genicom Matrix Printer manual Nak, Can

Negative Acknowledge		NAK
Data Structure ASCII	NAK	negative acknowledge
hex.	15
dec.	21

Description By sending the negative acknowledge code NAK a parity error (character with the wrong parity) is indicated in the data block to be transmitted and then the data block is deleted.

This code concerns only serial data transfer with ACK/NAK protocol.

For a detailed description see the documentation which comes with your printer.

Clear Print Buffer		CAN
Data Structure ASCII	CAN	clear print buffer
hex.	18
dec.	24

Description When the printer receives this code, the print buffer is completely cleared.

This code only clears the contents of the print buffer. It does not affect any control codes which have previously been sent to the printer.

96Miscellaneous