AT83C51SND1C_03 ATMEL [ATMEL Corporation], AT83C51SND1C_03 Datasheet - Page 77

• Manufacturer Part Number: AT83C51SND1C_03
• Description: Single-Chip Flash Microcontroller with MP3 Decoder and Human Interface
• Manufacturer: ATMEL [ATMEL Corporation]

Figure 53. MP3 Mode Audio Configuration Flow
Voice or Sound Playing
Figure 54. Voice or Sound Mode Audio Flows
Note:
4109E–8051–06/03
1. An under-run occurrence signifies that C51 core did not respond to the previous sample request interrupt. It may never
occur for a correct voice/sound generation. It is the user’s responsibility to mask it or not.
Program Audio Clock
Enable DAC System
Voice/Song Mode
Configure Interface
JUST4:0 = XXXXXb
Configuration
DUP1:0 = XX
AUDEN = 1
DSIZ = X
HLR = X
POL = X
Clock
In voice or sound playing mode, the operations required are to configure the PLL and
the audio interface according to the DAC selected. The audio clock is programmed to
generate the 256·Fs or 384·Fs as for the MP3 playing mode. The data flow sent by the
C51 is then regulated by interrupt and data is loaded 4 Bytes by 4 Bytes. Figure 54
shows the configuration flow of the audio interface when in voice or sound mode.
Set MSREQ & MUDRN
Load 8 Samples in the
Enable Interrupt
Program Audio Clock
Wait for DAC
Select Audio
Audio Buffer
Configure Interface
Enable Time
JUST4:0 = XXXXXb
EAUD = 1
Configuration
SRC = 1
MP3 Mode
DSIZ = X
HLR = X
POL = X
SRC = 0
1
Enable Data Request
Enable DAC System
DAC Set-up Time
Load 4 Samples in the
AUDEN = 1
DRQEN = 1
Service Routine
Sample Request?
Audio Interrupt
Wait For
Clock
Audio Buffer
SREQ = 1?
AT8xC51SND1C
Under-run Condition
1
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