Avision AV3200U+ (DF-0902H) - Manual (Page 58)

Note:
1 Within the specified timeout period, if you load your
document to the feeder, the scanner starts scanning
automatically.
2 If your scanner has a flatbed option and you place your
paper on the flatbed, after the timeout period, you need
to click the Scan button on the TWAIN user interface to
start scanning.
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