Datalogic MAGELLAN 3200VSI, Справочное руководство

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34 Magellan™ 3200VSI
Image Capture to the Host by Host Command
This feature is only available for RS-232 and USB COM interfaces.
NOTE
If the USB COM interface has been selected, follow the
USB-COM
Interface Setup on page 71
instructions in the
Interface Related
Features on page 39
chapter of this guide.
The host command format is as follows:
P<cnt>pSBC
where:
P
- ASCII 'P' used as preamble of pass-through commands
<cnt>
- binary value of 4 indicating 4 bytes to follow
p
- ASCII lowercase 'p' ; command to take a picture
S
- size value of image as ASCII character
‘S’ == uses scanner's configuration value
‘0’-VGA, (640X480)
‘1’-WVGA, (752X480)
‘2’-SXGA, (1280x1027)
‘3’-CIF (320x240)
B
- brightness value in ASCII
‘B’ == uses scanner's configuration value CI_IMAGE_BRIGHTNESS 
else ‘0’ thru’9’ specifies brightness
C
- contrast value in ASCII
‘C’ == uses scanner configuration value CI_IMAGE_CONTRAST

else ‘0’ thru’9’ specifies contrast
IF the image is of a type the scanner supports, capture and transmission occurs,
and the command is of proper format

THEN
The scanner will transmit an ACK (0x06) to the Host in response to this
command.
The image data transmission starts with a 4 byte binary field representing
(Big Endian) number of bytes to follow.
If the “number of bytes to follow” value is zero, there was a problem with
generating the image and the request should be retried.
ELSE
The scanner will transmit a BEL (0x07) to the Host in response to this com-
mand.
ENDIF