MSM9810 Datasheet, PDF (11/32 Pages) OKI electronic componets – 8-channel Mixing OKI ADPCM Type Voice Synthesis LSI

¡ Semiconductor
MSM9810
FUNCTIONAL DESCRIPTION
1. User Specification Phrase
A maximum of 256 phrases can be selected with user specification phrases. User specification
phrases are stored in the voice management area of external ROM. Merely by selecting a phrase,
sampling frequency and the start and stop address of voice are controlled.
The MSM9810 can directly specify a start address or stop address externally without using user
specification phrases. Only channels 1 to 4 can be used for directly specifying a start address or
stop address externally.
2. Playback Time and Memory Capacity
Table 2.1 shows the configuration of external ROM. The capacity of an actual voice data ROM is
different from the indicated ROM capacity.
Table 2.1 ROM Configuration
Address management area (16Kbits)
Voice data area or
Phrase Controll Table area
Playback time depends on external memory capacity, sampling frequency, and the playback
system. The relationship is shown below.
Playback time = ^{1.024 ¥ (memory capacity –16) (Kbits)} (Seconds)
Sampling frequency (kHz) ¥ bit length
(Bit length is ADPCM, ADPCM2...4bits, PCM...8bits)
For example, when one 8 Mbits ROM is used with a 16 kHz sampling frequency in a 4-bit ADPCM
type, the playback time becomes as follows.
Playback time= ^{1.024 ¥ (8192–16) Kbits} =.. 131 seconds
16 (kHz) ¥ 4 (bit)
In the above equation, the playback time when the Phrase Controll Table function is not used is
shown.
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