BCLKR
Bit Clock, Receive (Pin 26)
When used in the Long Frame Sync or Short Frame Sync mode, this pin accepts any bit clock frequency
from 64 to 5120 kHz. This pin may be used for applying an external 256 kHz clock for sequencing the
analog signal processing functions of this device. This is selected by the SCP port at BR0 (b7).
FSR
Frame Sync, Receive (Pin 27)
When used in the Long Frame Sync or Short Frame Sync mode, this pin accepts an 8 kHz clock that
synchronizes the input of the serial ADPCM data at the DR pin. FSR can operate asynchronous to FST
in the Long Frame Sync or Short Frame Sync mode.
FST (FSR)
BCLKT (BCLKR)
DT
1
2
3
4
5
6
7
8
DR
DON'T CARE
1
2
3
4
5
6
7
8
DON'T CARE
Figure 2-3. Long Frame Sync — 64 kbps PCM Data Timing
FST (FSR)
BCLKT (BCLKR)
DT
1
2
3
4
DR
DON'T CARE
1
2
3
4
DON'T CARE
Figure 2-4. Long Frame Sync — 32 kbps ADPCM Data Timing
FST (FSR)
BCLKT (BCLKR)
DT
1
2
3
DR
DON'T CARE
1
2
3
DON'T CARE
Figure 2-5. Long Frame Sync — 24 kbps ADPCM Data Timing
2-14
MC145540
MOTOROLA