FEDL22620-01
ML22620
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Memory Allocation and Creating Sound Data
The serial flash memory is partitioned into four data areas: sound (i.e., phrase) control area, test area, sound area, and edit
ROM area.
The sound control area manages the sound data in the ROM. It contains data for 4,096 phrases.
The sound area contains actual waveform data.
The edit ROM area contains data for effective use of sound data. For the details, refer to the section of "Edit ROM
Function".
The edit ROM area is not available if the edit ROM is not used.
The ROM data is created using a dedicated tool (Speech LSI Utility).
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Playback time and memory capacity
The playback time depends on the number of phrases, memory capacity, sampling frequency, and playback algorithm. The
relationship is shown below. However, this is the playback time when the edit ROM function is not used.
When the number of phrases is 1024, the sampling frequency is 16kHz, and the HQ-ADPCM algorithm is selected, the
playback time will be approximately 81 seconds.
Configuration of Serial Flash Memory Data (4Mbit)
Edit ROM area
Depends on creation of ROM
Test area
0x00000
0x0007F
0x7FFFF
0x00080
Sound area
Sound control area (*)
(The number of phrases can be set
with the dedicated tools.)
0x0207F
0x02080
(*) When the number of phrases is set to 1024
The number of phrases can be set from 1024 to 4096 in 1024 units
using the dedicated tools.
1.024 × (Memory Capacity (kbit)-(0.0625 × Number of Phrases)-0.625)
Sampling frequency (kHz) × bit length
Playback Time =
(sec)
1.024 × (4096(kbit)- (0.0625×1024) - 0.625)
16 (kHz) × 3.2 (bit) (average)
Playback Time =
≒
81 (sec)
20/115
Summary of Contents for LAPIS Semiconductor ML22620
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