Epson Arm S1C31 Series Technical Manual page 314

4) sp_state_play
This is the state in which the HWP is performing playback output. This state allows issuance of the Sound Stop,
Pause, or Mute command. When the sound data ends or the Sound Stop command is issued, the HWP stops
playback output and returns to sp_state_idle state. When the Pause command is issued, the HWP transits to sp_
state_pause state to pause playback output. When the Mute command is issued, the HWP transits to sp_state_
mute state to mute the sound.
5) sp_state_pause
This is the state in which the playback output is paused. This state allows issuance of the Release Pause or
Sound Stop command. When the Release Pause command is issued, the HWP transits to sp_state_play state to
resume playback output. When the Sound Stop command is issued, the HWP terminates playback output and
returns to sp_state_idle state.
6) sp_state_mute
This is the state in which the playback output is being continued with the sound muted. This state allows is-
suance of the Release Mute or Sound Stop command. When the Release Mute command is issued, the HWP
transits to sp_state_play state to restore the volume. When the sound data ends or the Sound Stop command is
issued, the HWP terminates playback output and returns to sp_state_idle state.
The current Ch.n operating state can be monitored by reading the STATE_n.STATE[15:0] bits (except hwp_
sleep). Furthermore, an interrupt can be generated when a state transition to the designated state occurs.
Sound play commands
Table 22.4.1.1 lists the Sound Play function commands.
Command
Sound Start
Sound Stop Immediately
Sound Stop after Current
Phrase
Pause Immediately
Pause after Current Phrase
Release Pause
Mute Immediately
Mute after Current Phrase
Release Mute
Each sound play command can be issued in the specific states. Follow the procedure below to issue a com-
mand.
1. Confirm that the STATE_n.STATE[15:0] bits = issuable state.
2. Confirm that the STATUS.READY bit = 1.
3. Configure the Sound Play function registers required to execute the command (if necessary).
4. Set the COMMAND_n.COMMAND[7:0] bits.
5. Write 1 to the HWPCMDTRG.HWP0TRG bit.
6. Wait until the HWPINTF.HWP0IF bit is set to 1 (interrupt).
7. Confirm that the STATE_n.STATE[15:0] bits = transit destination state (if necessary).
Playback start/stop
Single channel playback output start procedure
The following shows a Ch.n playback output start procedure:
1. Confirm that the STATE_n.STATE[15:0] bits = 0x0001 (sp_state_idle).
2. Confirm that the STATUS.READY bit = 1.
S1C31D41 TECHNICAL MANUAL
(Rev. 1.1)
Table 22.4.1.1 List of Sound Play Commands
Function
Start playback output
Stop playback output immediately
Stop playback output after ending current phrase
Pause playback output immediately
Pause playback output after ending current phrase sp_state_play sp_state_pause
Release pause state
Mute playback output immediately
Mute playback output after ending current phrase
Release mute state
Seiko Epson Corporation
22 HW Processor (HWP) and Sound Output (SDAC2)
Issuable state
sp_state_idle
sp_state_play,
sp_state pause,
sp_state_mute
sp_state_play,
sp_state pause,
sp_state_mute
sp_state_play sp_state_pause
sp_state_pause sp_state_play
sp_state_play
sp_state_play
sp_state_mute
(Command acceptable)
(Select command)
(Trigger to issue command)
(Occurrence of state transition)
(Command acceptable)
Transit
destination state
sp_state_play
sp_state_idle
sp_state_idle
sp_state_mute
sp_state_mute
sp_state_play
22-7