320
MC97F60128
ABOV Semiconductor Co., Ltd.
11.17.3 The Decoder Result Output of the FADPCM
The decoder result output data (DODRH/L) are a 16-bit binary format. The data will be output every decoder match
signal and the first data is 8000H after clear of decoder block by DIVS bit set to
‘1’. The match signal is generated
twice in the interval time which is set for a sampling frequency. The decoder result output is the result of decoding and
the average of previous and next data. The decoder data for the sampling frequency is calculated by the following
formula.
Decoder Data (DECDR[7:0]) = (System Clock (fx) ÷ Sampling frequency (fs) ÷ Divider)
– 1, Where the divider is one of
2, 4, 8 and 16.
X
1
2
4
3
4
1
2
4
0
Decoder
clock
Decoder
Counter
DECDR[7:0]
Decoder Result
Output Data
Match
0
Clear and Start
3
3
8
0
2
Decoder Match
Signal
1
0
Match
Match
X
Decoder Buffer
4
DECDR ÷ 2
8000H
(8000H + Data1) ÷ 2
Data1
------
ts: Sampling Time
Figure 11.99
Decoder Match Signal and Sampling Time
Decoder Result Output
Data (DODR[15:0])
Match
Decoder Match Signal
X
Clear and Start
8000H
(1
st
Data after Start)
Data(1)
Data(2)
Data(3)
Match
Match
Match
Match
Match
Match
Match
--------------------------
Data(n-3)
Data(n-2)
Data(n-1)
Data(n-1)+Data(n)
2
Data(n)
Match
Match
Match
Match
Match
Match
--------------------------
Data(n-2)+Data(n-1)
2
Data(n-3)+Data(n-2)
2
8000H+Data(1)
2
Data(1)+Data(2)
2
Data(2)+Data(3)
2
Data(3)+Data(4)
2
Voice Prompt End
Interrupt
Figure 11.100
Decoder Result Output Data
Содержание MC97F60128
Страница 17: ...17 MC97F60128 ABOV Semiconductor Co Ltd 4 Package Diagram Figure 4 1 100 pin LQFP 1414 Package...
Страница 18: ...18 MC97F60128 ABOV Semiconductor Co Ltd Figure 4 2 80 Pin LQFP 1212 Package...
Страница 19: ...19 MC97F60128 ABOV Semiconductor Co Ltd Figure 4 3 80 Pin LQFP 1414 Package...
Страница 20: ...20 MC97F60128 ABOV Semiconductor Co Ltd Figure 4 4 64 Pin LQFP 1414 Package...
