RS-232 Interface 11 - 13
ACK/NAK with ENQ
This combines the two previous options.
ACK/NAK with ENQ
XON/XOFF
An XOFF character turns the scanner transmission off until the scanner receives an XON character. There are two
situations for XON/XOFF:
The scanner receives XOFF before has it data to send. When the scanner has data to send, it waits up to
Host Serial Response Time-out for an XON character before transmission. If the scanner does not receive
an XON within this time, it issues an error indication and discards the data.
The scanner receives XOFF during a transmission. Data transmission then stops after sending the current
byte. When the scanner receives an XON character, it sends the rest of the data message. The scanner
waits indefinitely for the XON.
XON/XOFF