ReQuest Multimedia VideoReQuest, Protocol Manual, Page: 16 / 20

VideoReQuest Protocol Guide v1.1.2 - 5/18/04
Phone (518) 899-1254
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Example:
Let’s say you received the following string from the VideoReQuest:
FC h , A0 h , 0A h , 84 h , 00 h , 00 h , 00 h , 07 h , 00 h , Horror, 00 h
We know from the format explained on the previous page that
84 h is the Command
Subtype . From the table of subtypes on the previous page, we know that 84 h indicates
that you are receiving the Browse Column 1 Data . Therefore, we extract Horror from
the data portion and save that in our Browse Column 1 Data variable.
Special Data Formats:
Browse List Title:
The Browse List Title is sent in chunks, delimited by a NULL character ( 00 h ). For
example, if you are inside the Genres list, the data portion of the string sent by the
VideoReQuest will look like this:
Home[00 h ]Genres[00 h ] . This allows you to use
just the final portion to show the current list title, or the entire thing to show the full
hierarchy.
List Size, Page UP/DOWN Flags, and Cursor Position:
The List Size, Page UP/DOWN Flags and Cursor Position for the Browse and
Player pages are sent by the VideoReQuest in 1 string. The first 4 bytes of the string
are the
List Size , the next byte is the Page UP/DOWN Flag , and the final 2 bytes
are for the Cursor Position .
List size is calculated as follows:
256
3
×BYTE1+256
2
×BYTE2+256×BYTE3+BYTE4
Page UP/DOWN flags could be one of the following:
Value Description
00 h No more lines exist above or below the current view
01 h More lines exist below the current view
02 h More lines exist above the current view
03 h More lines exist above AND below the current view
The 2 bytes for
Cursor Position are calculated as follows:
256×BYTE1 + BYTE2 = RESULT
The following values of
RESULT are possible:
Value Cursor on Line
1 1
2 2
4 3
8 4
16 5
32 6
64 7
128 8
Value Cursor on Line
256 1
512 2
1024 3
2048 4
4096 5
8192 6
16384 7
32768 8