msm7564-01 Oki Semiconductor, msm7564-01 Datasheet - Page 12

• Manufacturer Part Number: msm7564-01
• Description: A Single Chip 14.4 Kbps Data & Fax Modem
• Manufacturer: Oki Semiconductor

MSM7564-01
Received Signal Quality Monitor
Echo Canceler
Voice Output Function
Test Mode
Sleep Mode
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The modem indicates a state of received signal quality using the SQD bit of register 0D. If this bit
changes, an interrupt signal (STCHG) for controlling the microprocessor is generated. Furthermore,
it can read the bit error rate and receive level (stored in internal RAM) required for MNP class 10.
The modem has internal RAM for bulk delay and can cope with delays of up to 1.2 s for far-end echo.
The voice output is enabled by setting MODEMSET bit of register 06 to voice mode. In this case, voice
data of 7.2 kHz sampling of 8 bits must be written in 00, 01, and 02 registers with the rising edge of
RBTM (2.4 kHz).
The modem performs the internal local analog loop testing by the LALTST bit of register 07H. It also
performs external local analog loop testing by the LALTST bit of register 07H and by connecting
transmit analog output and receive analog input. Remote digital loop is available by the LOOP2 bit
of register 1EH.
It can output a 511PN pattern and 1 to 1 pattern for error test controlling PN511 and ERR11 bits of
register 1EH.
Error counts can be read controlling ERRCNT bit of register 1DH.
The modem supports a sleep function by controlling SLEEP bit of register 04H and SLEEP pin. It
provides two modes of sleep1 (clock generator is inactive at CKOEN = '1') and sleep2 (clock generator
is active at CKOEN = '0') controlled by CKOEN pin. Cancellation of sleep mode is controlled by
SOFTRST bit of register 04H and RST pin.
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