3.7.4 Request Commands
31)
FRAME NUMBER REQUEST
LD
Function:
The frame number which is currently being played is returned.
Format:
? F
Explanation:
Contents of the current Frame Register are returned.
During playback of a CAV disc, a 5-digit frame number is returned.
During playback of a CLV disc, a 7-digit frame number is returned.
(See
Appendix E-1
,
Notes
for details.) Correct values are not shown
if the player is not in
Random Access Mode
, or if the player is in the
lead-in or lead-out area of a disc.
As seen in the example, continuous frame numbers may not be
received due to timing delays between the computer and the
player. If a frame number code on the disc cannot be correctly
read, the previous value is used. An error (E04) is returned if this
query is sent to the player while a CD is playing.
Execution:
* Play Mode (CAV)
* Play Mode (CLV)
? F <C/R>
0 2 0 4 4 <C/R>
? F <C/R>
0 010442<C/R>
? F <C/R>
0 2 0 4 5 <C/R>
? F <C/R>
0 010446<C/R>
? F <C/R>
0 2 0 4 5 <C/R>
? F <C/R>
0 010502<C/R>
? F <C/R>
0 2 0 4 7 <C/R>
? F <C/R>
0 010507<C/R>
32)
CHAPTER NUMBER REQUEST
LD
Function:
The chapter number which is currently being played is returned.
Format:
? C
Explanation:
Contents of the Chapter Number Register are returned.
The chapter number is a 2-digit integer (00-79). Some LaserDiscs
are not encoded with chapter numbers. When playing a disc
without chapters, an error is returned when this request is issued.
Correct values will not be shown if the player is not in
Random
Access Mode
, or if the player is in the lead-in or lead-out area of a
disc. An error (E04) is returned if this query is sent to the player
while a CD is playing.
Execution:
* Play Mode
? C <C/R>
1 2 <C/R>
CLD-V2800 Level III • Chapter Three
CLD-V2800 Level III User’s Manual
TP 120
v. 1.0 • 10/95
3-31