Atmel AT83SND2C MP3 - Manual (Page 54)

Protocol Frame Description
5-50 AT83SND2CMP3 User Guide
7525A–MP3–07/05
Table 5-65 . FS_NAME Frame in response to FS_NAME Command
The File_Name is a UNICODE filename with extension already formatted: “song1.mp3”.
Byte 1 is low byte of unicode, Byte 2 is high byte of unicode.
Note:
1. Example: File_name “song1.mp3”, the unicode is 53h 00h 4Fh 00h 4Eh 00h 47h 00h
31h 00h 2Eh 00h 4Dh 00h 50h 00h 33h 00h.
2. When file name is only ‘\0’, it means that the root directory is empty.
PLAYER_TIME* Response Player playing time since the beginning of the file. This frame is the response to the
PLAYER_GET_TIME command.
Table 5-66 . PLAYER_TIME Frame
PLAYER_VOLUME* Response Player current digital and analog volume. This frame is the response to the
SYSTEM_VOLUME_UP, SYSTEM_VOLUME_DOWN and SYSTEM_SET_SOUND
command.
Table 5-67 . PLAYER_VOLUME Frame
Note: Refer to AT83SND2CMP3 datasheet for Master Analog Volume section DAC Master Playback Gain
Value (02h is -9dB, 20h is mute).
FS_FREAD_BLOCK_DATA*
Response
Player Response of FS_READ_BLOCK command. This commands send block of 512
bytes (data read in current selected file).
Frame Start Channel
Protocol
Command
Data
Length Data
CheckSu
m
7Eh
If not used,
FFh
82h N
Byte 0: Player Status (1 Byte)
Byte 1 to N-1: File_Name (N-1
bytes)
Yes
Frame Start Channel
Protocol
Command Data Length Data CheckSum
7Eh
If not used,
FFh
83h 03h
Byte 0: Player Status
Byte 1: Minute
Byte 2: Second
Yes
Frame
Start Channel
Protocol
Command Data Length Data CheckSum
7Eh
If not used,
FFh
87h 03h
Byte 0: MP3 Digital Volume Left
Byte 1: MP3 Digital Volume Right
Byte 2: MP3 Bass
Byte 3: MP3 Medium
Byte 4: MP3 Trebble
Byte 5: Master Analog Volume
Yes