when a time-out occurs.
ENQ
: If you select this option, the digital scanner waits for an ENQ character
from the host before transmitting data. If it does not receive an ENQ within the
Host Serial Response Time-out, the digital scanner issues an error indication
and discards the data. The host must transmit an ENQ character at least every
Host Serial Response Time-out to prevent transmission errors.
ACK/NAK with ENQ
: This combines the two previous options. For
re-transmissions of data, due to a NAK from the host, an additional ENQ is not
required.
XON/XOFF
: An XOFF character turns the digital scanner transmission off until
the scanner receives an XON character. There are two situations for
XON/XOFF:
The digital scanner receives an XOFF before has 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 it does not receive the XON
within this time, the digital scanner issues an error indication and discards
the data.
The digital scanner receives an XOFF during a transmission. Data
transmission then stops after sending the current byte. When the digital
scanner receives an XON character, it sends the rest of the data message.
The digital scanner waits indefinitely for the XON.
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Copyright 2013 Unitech Electronics Co., Ltd. All rights reserved. Unitech is a registered trademark of Unitech Electronics Co., Ltd.
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