Atmel AT83SND2C MP3 - Manual (Page 39)

Protocol Frame Description
AT83SND2CMP3 User Guide 5-35
7525A–MP3–07/05
SYSTEM_ENTER_HID_MODE Ask the Player to enter the HID mode (only available with UART link). The Player shall
be in IDLE state to enter HID mode (no Mass Storage, no Playing).
When connected in this way, the Player acts only as USB-UART bridge. This mode
allow the Remote Controller to send and receive any binary/protocol information from/to
UART.
To exit from this mode, Remote Controller have to perform an hardware Player Reset or
unplug the USB cable.
Table 5-22 . SYSTEM_ENTER_HID_MODE Command Format
Figure 5-2 . Player USB-UART Bridge
Frame Start Channel
Protocol
Command Data Length Data CheckSum
7Eh
Not used,
FFh
0Fh 00h No Yes
Remote Controller Player
UART
Player RESET
USB
USB HID Class
Atmel HID .DLL
PC Application with
interface simple
(‘putchar’, ‘getchar’)
PC
Brigde
USB / UART