ETX/ACK protocol
ETX (hex03) Block end character
ACK (hex06) Acknowledgement informing the host that further data may be transmitted.
XON/XOFF This protocol is used in addition to data flow control and printer status
handling.
HandThr.=ON An ETX is not acknowledged by ACK before all previously arrived data
have been printed.
HandThr.=OFF When the printer receives an ETX, it returns an ACK to the host. Any
previously sent data or blocks may still be present in the printer buffer.
ACK/NAK protocol
STX (hex02) Clears any previous error status.
ETX (hex03) Block end character
ENQ (hex05) Printer status enquiry (see ENQ/STX).
ACK (hex06) Acknowledgement character; block was transmitted successfully.
NAK (hex15) Block transmission error.
DEL (hex7F) Deletes the whole block; acknowledged by ACK or NAK.
HandThr.=ON Does not filter out the STX, ENQ, ETX, DEL characters from the data
stream (transparence). However, they are also used for block control.
HandThr.=OFF The STX, ENQ, ETX, DEL characters are filtered out from the data stream
at the interface and used for control.
XON/XOFF control is not available with the ACK/NAK protocol.
Reference manual
Interfaces
189