Alcorn Mcbride AM-4, Справочное руководство по аппаратному и программному обеспечению

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48 File Types and Storage
Special Play List Command Summary
Special command characters further modify the behavior of the AM-4 Digital Audio
Machine. These characters are:
Char Meaning
U Uninterruptible. Causes the AM-4 Digital Audio Machine to ignore the
Resume input and serial Play command while playing. It still processes them
when waiting or paused.
I Interruptible. Allows the Resume input or serial Play command to skip to the
next track. This is the power-up default.
^ Wait. Unit waits until a Resume, Play, or repeated file select of the current
playlist number is received, then continues to the next command in the playlist.
< Repeat entire Play List. The only way to stop the Play List from looping is to
use the Stop input or serial command, or to start another file. Anything in the
Play List after the ‘<’ character is ignored.
; Comment. Ignore all characters until the next carriage return.
Commands may be entered into the Play List in either upper or lower case. All text
following a semicolon (;) is interpreted as comments, until the next carriage return.
You may put anything you want in comments, including the special command
characters normally used in the Play List.
File Select inputs and
serial Play command
change functions when
using a Play List.
When the AM-4 Digital Audio Machine is processing a Play List, reactivating the same
File Select inputs or sending the serial play command take on different meanings ,
depending upon whether the unit is playing, paused, or waiting. Here is how they behave:
Mode Interruptible Uninterruptible
Playing Immediately play next file Ignored
Paused Resume play Resume play
Waiting Play next file Play next file
Asserting and releasing the Pause input while the unit is in the Waiting state of a
Play List will also resume play.
One thing to be cautious of is the unintended endless loop or uninterruptible wait. For
example, if a Play List contains a U followed by an Loop Play command, it doesn’t
matter how many more tracks may occur in it, there is no way to get to them! When
using the U command, always include an I command before the next Loop Play or
W, unless this is the desired behavior. Of course, you can always terminate the loop
or wait with a stop command, or by selecting a different file.
Play Lists may contain references to other Play Lists, but as soon as such a reference
is encountered the new Play List begins execution, and the old one is abandoned.