User manual

® Waves System V 1346 - 2012
I.D. AL - My Music Player - Audio Player - User manual
10 - RS232 Serial link protocol
My Music Player can communicate with other devices. It receives commands on the Rx input and sends
data through the Tx output. The player complies with the RS232 norm.
Speed (baud) : 115.200 / Data : 8 bits / No parity / one bit stop
10.1 – Reception protocol
The reception protocol allows the player to receive orders to start reading a file or adjust volume level.
The reception protocol is made of a 4 byte frame.
Byte 1 - Command
Byte 2 and 3 - Data of the command
Byte 4 – Complementary Data following the command
Reminder:
- a byte is composed of 8 bits: b7 b6 b5 b3 b2 b1 b0
- a binary representation is noted: 00000000b or in hexadecimal: 0x00 or 0x0000
Byte 1 (Command) – Value between 0x00 and 0xFF
Byte 2 and 3 (Data) – Value between 0x0000 and 0xFFFF
Byte 4 (Data option) – Value between 0x00 and 0xFF
Commands requiring only one or two Bytes (Play, Stop ...) are completed with 3 or 2 bytes 0xFF to get a
4 bytes frame.
The maximum lead time between the sending of 2 bytes is 500ms.
Example for 2 frames of 4 bytes :
- 31 -
Frame of 4 bytes Frame of 4 bytes
500ms
Maxi
Byte 1
Byte 2