73K224AL 데이터 시트보기 (PDF) - TDK Corporation

부품명

상세내역

일치하는 목록

73K224AL

V.22, V.21, Bell 212A, Bell 103 Single-Chip Modem with Integrated Hybrid

TDK Corporation 

73K222BL

V.22, V.21, Bell 212A, Bell 103

Single-Chip Modem with Integrated Hybrid

FUNCTIONAL DESCRIPTION (continued)

PARALLEL BUS INTERFACE

Four 8-bit registers are provided for control, option

select and status monitoring. These registers are

addressed with the AD0, AD1, and AD2 multiplexed

address lines (latched by ALE) and appear to a control

microprocessor as four consecutive memory locations.

Two control registers and the tone register are

read/write memory. The detect register is read only and

cannot be modified except by modem response to

monitored parameters.

SPECIAL DETECT CIRCUITRY

The special detect circuitry monitors the received

analog signal to determine status or presence of carrier,

call-progress tones, answer tone and weak received

signal (long loop condition). An unscrambled mark

request signal is also detected when the received data

out of the DPSK demodulator before the descrambler

has been high for 165.5 ms ± 6.5 ms minimum. The

appropriate detect register bit is set when one of these

conditions changes and an interrupt is generated for all

purposes except long loop. The interrupts are disabled

(masked) when the enable interrupt bit is set to 0.

DTMF GENERATOR

The DTMF generator will output one of 16 standard

tone pairs determined by a 4-bit binary value and TX

DTMF mode bit previously loaded into the tone register.

Tone generation is initiated when the DTMF mode is

selected using the tone register and the transmit enable

(CR0 bit D1) is changed from 0 to 1.

4

Share Link: