MT9122
Pin Description (continued)
Pin #
17/18
Name
S4/S3
Description
Preliminary Information
Selection of Echo Canceller B Functional States (Input):
Controllerless Mode: Selects Echo Canceller B functional states according to Table 2.
Controller Mode: S4 and S3 pins become SCLK and CS pins respectively.
17
18
19/20
SCLK
CS
S2/S1
Serial Port Synchronous Clock (Input):
Data clock for the serial microport interface.
Chip Select (Input):
Enables serial microport interface data transfers. Active low.
Selection of Echo Canceller A Functional States (Input):
Controllerless Mode: Selects Echo Canceller A functional states according to Table 2.
Controller Mode: S2 and S1 pins become DATA2 and DATA1 pins respectively.
19
DATA2
Serial Data Receive (Input):
In Motorola/National serial microport operation, the DATA2 pin is used for receiving data. In
Intel serial microport operation, the DATA2 pin is not used and must be tied to Vss or Vdd.
Serial Data Port (Bidirectional):
In Motorola/National serial microport operation, the DATA1 pin is used for transmitting data. In
Intel serial microport operation, the DATA1 pin is used for transmitting and receiving data.
Delayed Frame Pulse Output (Output):
In ST-BUS operation, this pin generates a delayed frame pulse after the 4th channel time slot
and is used for daisy-chaining multiple ST-BUS devices. See Figures 5 to 8.
In SSI operation, this pin outputs logic low.
20
DATA1
21
F0od
22
23
VDD
Sout
Positive Power Supply:
Nominally 5 volts.
Send PCM Signal Output (Output):
128 kbit/s to 4096 kbit/s serial PCM output stream. Data may be in either companded or 2’s
complement linear PCM format. Two PCM channels are time-multiplexed on this pin. These
are the Send Out signals after echo cancellation and Non-linear processing. Data bits are
clocked out following SSI or ST-BUS timing requirements.
Receive PCM Signal Output (Output):
128 kbit/s to 4096 kbit/s serial PCM output stream. Data may be in either companded or 2’s
complement linear PCM format. Two PCM channels are time-multiplexed on this pin. This
output pin is provided for convenience in some applications and may not always be required.
Data bits are clocked out following SSI or ST-BUS timing requirements.
Frame Pulse (input):
In ST-BUS operation, this is a frame alignment low going pulse. SSI operation is enabled by
connecting this pin to Vss.
24
Rout
25
F0i
26
BCLK/C4i Bit Clock/ST-BUS Clock (Input):
In SSI operation, BCLK pin is a 128 kHz to 4.096 MHz bit clock. This clock must be
synchronous with ENA1, ENA2, ENB1 and ENB2 enable strobes.
In ST-BUS operation, C4i pin must be connected to the 4.096MHz (C4) system clock.
27/28 CONFIG1/ Device Configuration Pins (Inputs).
CONFIG2
When CONFIG1 and CONFIG2 pins are both logic 0, the MT9122 serial microport is enabled.
This configuration is defined as Controller Mode. When CONFIG1 and CONFIG2 pins are in
any other logic combination, the MT9122 is configured in Controllerless Mode. See Table 3.
Notes:
1. All unused inputs should be connected to logic low or high unless otherwise stated. All outputs should be left open circuit when not used.
2. All inputs have TTL compatible logic levels except for MCLK, Sin and Rin pins which have CMOS compatible logic levels and PWRDN
pin which has Schmitt trigger compatible logic levels.
3. All outputs are CMOS pins with CMOS logic levels.
8-20
MITEL [ MITEL NETWORKS CORPORATION ]
