Filter
Top Products
Chapter 7: Programming 7-43
If you enable ACK/NAK, each message sent to the host terminal must
be acknowledged before sending the next message. Receiving the
message properly causes an ACK to be sent, and if there are any errors,
a NAK is sent instead and the scanner/scale sends the message again.
Also, any valid message other than NAK or XOn/XOff, if enabled,
serves as an ACK as long as the message from the scanner/scale is
completed before the host terminal starts sending the valid message to
the scanner/scale.
An XOff message turns the scanner transmitter off until the
scanner/scale receives an XOn message. An XOn message can be
received at any time. If the scanner/scale is sending a message when it
receives an XOff, since these messages can be received any time, data
transmission stops after sending the current byte. When the
scanner/scale receives the next XOn it sends the remainder of the
message. The scanner/scale does not acknowledge XOff and XOn
messages with ACK or NAK messages.
You select the interface by scanning the appropriate Hex 0 through
Hex 3 tag. The default is None.
Check Digit
The Check Digit parameter permits you to control the transmission of
UPC-A, UPC-E, EAN-8, and EAN-13 check digits. Scan the
appropriate Hex 0 through Hex 3 tags to enable or disable UPC-A,
UPC-E, EAN-8, and EAN-13 check digits. The default is enable UPC-
A, EAN-8, and EAN-13 and disable UPC-E.
Note:
Although this is an RS-232 Parameters worksheet, the Check
Digit parameter also applies to UPC-E when using OCIA
communications.