Newland NLS-EM1300, Руководство по интеграции

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nlscan.com Page 17
Electrical Interface
Output Signals
Here are the descriptions of the output signals, such as Beeper, LED and inter-character timeout. They can be
used to detect the status of the scanning, message uploading and the state of the Engine.
LED Output
When the Engine completes the initialization, the LED line is high. The LED line goes low for 150 ms after a
successful reading and, if programmed, transmission of the code message.
Beeper Output
Table below is the de fi nitions of the beeper outputs:
Beep Pattern De fi nition
Low-higher-higher-higher Power ON completed
1 beep Successful reading of an ordinary barcode
2 beeps Successful reading of a programming barcode
The message upload format is in binary. It is the binary value of the decoded barcode value including pre fi x,
suf fi x, and so on.
Inter-Character Timeout is used to determine the end of barcode message.
Host could use inter-character timeout to determine the end of data upload. An inter-character timeout means
the longest delay time between 2 consecutive (binary) characters in a sequence of (binary) characters sent
over serial line. It is usually enabled only after the fi rst character is received to avoid unwanted timeout
events during the waiting of a message.
The inter-character timeout value should be set to about 5 times of a character
’
s transmission time. When
the inter-character timeout occurs, it is the end of data upload. For example, 5 ms can be used as an inter-
character timeout for the baud rate of 9600, 8 data bit, no parity bit, and one stop bit.
Inter-Character Timeout