Atmel AT83SND2C MP3 User Manual
Page 33

Protocol Frame Description
AT83SND2CMP3 User Guide
5-29
7525A–MP3–07/05
AT83SND2CMP3 frame response is SYSTEM_ACK frame.
Table 5-4 . SYSTEM_GET_STATUS Frame Format
SYSTEM_AUDIO_OUTPUT
Command
Select Player Audio Output:
Headset
Power Amplifier
The default configuration is Headset and Power Amplifier activated after reset.
Table 5-5 . SYSTEM_AUDIO_OUTPUT Frame Format
Table 5-6 . AUDIO_OUTPUT Format
Note:
The Audio output “None” will power off the Audio Headset capacitors (from VDD/2 to 0V).
The Audio output None shall be used only before a hardware reset to avoid any ‘plop’ on
audio headset.
SYSTEM_SELECT_MEMORY
Command
Select Memory and mount file system FAT on memory. Player response is
SYSTEM_ACK frame.
When FAT is installed on selected memory, player’s status byte is updated with:
FNA set (File name available, Table 5-1 . Player STATUS Description). This flag is
set when FAT install is OK. Then Player is ready to process the ‘PLAY’ command.
MERROR set (Memory Error, Table 5-1 . Player STATUS Description). This flag is
set when memory initialization is KO or card is not present (for memory card slot).
MNF is set (Memory not formated, Table 5-1 . Player STATUS Description). This flag
is set when selected memory is not formated.
Frame Start
Channel
Protocol
Command
Data Length
Data
CheckSum
7Eh
Not used,
FFh
02h
00h
No
Yes
Frame Start
Channel
Protocol
Command
Data Length
Data
CheckSum
7Eh
Not used,
FFh
03h
01h
AUDIO_OUTPUT
(1 byte)
Yes
Audio Output
AUDIO_OUTPUT Parameter
Value (1 byte)
None
00h
Headset
01h
Reserved
02h
Headset and Power
Amplifier
03h