Motorola PL3307, Руководство по интеграции

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9 - 36 PL3307 Decoder Integration Guide
Code 39 Buffering - Scan & Store
Parameter # 71h
This feature allows the decoder to accumulate data from multiple Code 39 symbols.
Selecting the Scan and Store option (Buffer Code 39) temporarily buffers all Code 39 symbols having a leading
space as a first character for later transmission. The leading space is not buffered.
Decoding a Code 39 symbol with no leading space transmits in sequence all buffered data in a first-in first-out
format, plus the “triggering” symbol. See the following pages for further details.
Select Do Not Buffer Code 39 to transmit all decoded Code 39 symbols immediately without storing them in
the buffer.
This feature affects Code 39 only. If selecting Buffer Code 39 , we recommend configuring the decoder to
decode Code 39 symbology only.
While there is data in the transmission buffer, you cannot select Do Not Buffer Code 39 . The buffer holds
200 bytes of information.
To disable Code 39 buffering when there is data in the transmission buffer, first force the buffer transmission
(see
Transmit Buffer on page 9-37 ) or clear the buffer.
Buffer Data
To buffer data, enable Code 39 buffering and scan a Code 39 symbol with a space immediately following the
start pattern.
•
Unless the data overflows the transmission buffer, the decoder issues a low/high beep to indicate
successful decode and buffering. (For overflow conditions, see
Overfilling Transmission Buffer on page
9-37 .)
•
The decoder adds the decoded data excluding the leading space to the transmission buffer.
•
No transmission occurs.
Clear Transmission Buffer
To clear the transmission buffer, scan the Clear Buffer bar code below, which contains only a start character, a
dash (minus), and a stop character.
•
The decoder issues a short high/low/high beep.
•
The decoder erases the transmission buffer.
•
No transmission occurs.
Buffer Code 39 (Enable)
(01h)
*
Do Not Buffer Code 39 (Disable)
(00h)