Special Data Formats - ReQuest Multimedia VideoReQuest Protocol Manual

Example:
Let's say you received the following string from the VideoReQuest:
FCh, A0h, 0Ah, 84h, 00h, 00h, 00h, 07h, 00h, Horror, 00h
We know from the format explained on the previous page that 84h is the Command
Subtype. From the table of subtypes on the previous page, we know that 84h 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 (00h). For
example, if you are inside the Genres list, the data portion of the string sent by the
VideoReQuest will look like this: Home[00h]Genres[00h]. 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:
3
256 ×BYTE1+256
Page UP/DOWN flags could be one of the following:
Value Description
00h No more lines exist above or below the current view
01h More lines exist below the current view
02h More lines exist above the current view
03h 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
2
4
8
16
32
64
128
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2
×BYTE2+256×BYTE3+BYTE4
1
2
3
4
5
6
7
8
10 -
-
VideoReQuest Protocol Guide v1.1.2 - 5/18/04
Value Cursor on Line
256 1
512 2
1024 3
2048 4
4096 5
8192 6
16384 7
32768 8
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