Xerox WorkCentre Pro 423, Service Manual

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03/02 Level 2 Troubleshooting
WorkCentre Pro 423/428 2-99 CHAPTER 2 TROUBLESHOOTING
2.3.2.5.3 Presentation (B channel)
For the normal sequence of the Presentation protocol, see "Presentation" in the B-channel
sequence.
The Presentation layer exchanges image information in pages. The reception side declares
receiving capabilities and the transmission side declares necessary functions from the
capabilities for transmitting image information. Page contents (document size, resolution,
and other) can be known by analyzing a CDUIP signal. The CDUIP signal is recorded as
"PageD" in the Presentation protocol.
Table 11 Signals Used in Presentation Protocol (Layer 6 of B channel)
Signal Meaning Description
PressD Capability declaration Capabilities of the transmission and reception sides
(Paper size, resolution, encoding, and other)
DocuD Fax page declaration Transmission of fax document page
PageD Page contents Size (fast scan and slow scan) and resolution
TextU Image information Image information
2.3.2.5.3-1 Command FIF
The CDUIP (PageD) contains the information of a page to be transmitted. Therefore, the
page size and resolution can be known by analyzing this command. See the section of the
CDUIP signal.
The CDUIP signal contains the page size and other information elements. Necessary
information elements are added according to the contents of the communication elements.
CDUIP FIF indicates each information element by "iden information element length
(number of bytes in a hex format) + information element contents." The example below
shows FIF of CDUIP(PageD).
A2
16
02
01
02
31
11
A4
08
80
02
26
C0
80
02
36
81
A6
Identifier of information element "Page descriptor"
Byte length of information element "Page descriptor": 16h = 22 bytes
Identifier of information element "Layout object type"
Byte length of information element "Layout object type": 01h = 1 byte
Layout object type: 02h = Page
Identifier of information element "Layout descriptor"
Byte length of information element "Layout descriptor": 11h = 17 bytes
Identifier of information element "Document size"
Byte length of information element "Document size": 08h = 8 bytes
Identifier of information element "Fast scan width"
Byte length of information element "Fast scan width": 02h = 2 bytes
Contents of "Fast scan width": Fast scan width value with next byte
Fast scan width: 26C0h MBU
Identifier of information element "Slow scan width"
Byte length of information element "Slow scan width": 02h = 2 bytes
Contents of "Slow scan width": Slow scan width value with next byte
Slow scan width: 3681h MBU
Identifier of information element "Attribute"
:
Byte 1
Byte 2