11.13. USB INTERFACE CIRCUIT
This unit have one USB port for using PC programming. ASIC have USB 1.1 controller inside, so this unit make up USB interface
only ASIC and USB connector.
11.14. OGM INTERFACE CIRCUIT
The TES/TEM824 model incorporates the functions of OGM, CNG and DTMF detection. At the OGM recording, it changes the
analog sound in the DSP of the ASIC into a digital signal of 16bits by A/D conversion. Then, the data is compressed (encoded) and
stored in a 4M serial flash. Conversely, when being recovered the data stored in the 4M serial flash are decompressed to 16-bit
digital data, and then reproduced as an analog sound after the D/A conversion. The recording/reproducing is achieved by
connecting the path from external line through the cross point to the ASIC.The waveform coding method used at the
recording/reproducing stage is the LD-ADPCM method. The DSP compresses the sound and stores the 4M serial flash using the
memory management software in the DSP. The unit has the recording/reproducing function of 1CH as an initial mounting.The
recording time of the OGM is three minutes at maximum.
Also, the CNG and DTMF detection are the functions operated in conjunction with the OGM and realized by the DSP in the ASIC.
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KX-TES824LA / KX-TEM824LA /
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