Chapter 5: Programming 5-49
Interface Control
The Interface Control parameter permits control of the transfer of data between the scanner and
the host terminal. The options are None, enable ACK/NAK, enable XOn/XOff, and enable
both ACK/NAK and XOn/XOff.
If enable ACK/NAK is selected, 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 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 is completed before the host terminal starts sending the valid
message to the scanner.
An XOff message turns the scanner transmitter off until the scanner receives an XOn message.
An XOn message can be received at any time. If the scanner 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 receives the next XOn, it sends the remainder of
the message. The scanner does not acknowledge XOff and XOn messages with ACK or NAK
messages.
Select the interface by scanning the appropriate
Hex 0
through
Hex 5
tag.
Check Digit
The Check Digit parameter permits control of the transmission of UPC–A, UPC–E, EAN–8,
and EAN–13 check digits. Scan the appropriate Hex tag (
Hex 0
to
Hex F
) to independently
enable or disable UPC–A, UPC–E, EAN–8, and EAN–13 check digits. The default is
Hex 1
—
Enable UPC–A, EAN–8, and EAN–13; Disable UPC–E.
RS-232 Prefix Byte
22774
Prefix Byte
A
ASCII Code
B
0
Disable
1
Enable
0 - 7
Hex Character
(ASCII Code Chart)
0 - F
Hex Character
(ASCII Code Chart)
0
Default
2
Your Program
Prefix Byte
A
RS-232
Prefix Byte
2
2
ASCII Code
B
The RS-232 Prefix Byte programming mode controls the use of prefix bytes. If an RS-232
Prefix Byte is used, it is the leading character in each message sent to the host terminal.
Following it is the message data. Refer to the “Parameter Defaults” section earlier in this
chapter for the factory defined default value of each programming parameter.
Summary of Contents for RealPOS
Page 1: ...NCR RealPOSTM Presentation Scanner 7893 Release 1 0 User Guide 27355 B005 0000 1917 Issue A...
Page 16: ......
Page 18: ......
Page 36: ......
Page 132: ......
Page 152: ......
Page 156: ......
Page 164: ......
Page 166: ...B 2 Appendix B NCR Scanner Programming Tags Volume Adjustment 11817 Reset 11818...
Page 167: ...Appendix B NCR Scanner Programming Tags B 3 Default R0046 Programming Mode R0042 End R0043...
Page 171: ...Appendix B NCR Scanner Programming Tags B 7 Hex 0 R0048 Hex 1 R0049...
Page 172: ...B 8 Appendix B NCR Scanner Programming Tags Hex 2 R0050 Hex 3 R0051 Hex 4 R0052...
Page 173: ...Appendix B NCR Scanner Programming Tags B 9 Hex 5 R0053 Hex 6 R0054 Hex 7 R0055...
Page 174: ...B 10 Appendix B NCR Scanner Programming Tags Hex 8 R0056 Hex 9 R0057 Hex A R0058...
Page 175: ...Appendix B NCR Scanner Programming Tags B 11 Hex B R0059 Hex C R0060 Hex D R0061...
Page 180: ......
Page 182: ......
Page 184: ......
Page 187: ......