Advance Information
MT9074
Pin Description
Pin #
Name
Description
68Pin 100 Pin
PLCC MQFP
1
66
OSC1
OSC2
Oscillator Input. This pin is either connected via a 20.000 MHz crystal to OSC2
where a crystal is used, or is directly driven when a 20.000 MHz. oscillator is
employed.
2
67
Oscillator Output. Connect a 20.0 MHz crystal between OSC1 and OSC2. Not
suitable for driving other devices.
3
4
5
68
69
70
V
Negative Power Supply (Input). Digital ground.
SS
V
Positive Power Supply (Input). Digital supply (+5V ± 5%).
DD
CSTo
Control ST-BUS Output. CSTo carries serial streams for CAS and CCS
respectively a 2.048 Mbit/s ST-BUS status stream which contains the 30 receive
signalling nibbles (ABCDZZZZ or ZZZZABCD). The most significant nibbles of
each ST-BUS time slot are valid and the least significant nibbles of each ST-BUS
time slot are tristated when control bit MSN (page 01H, address 1AH, bit 1) is set
to 1. If MSN=0, the position of the valid and tristated nibbles are reversed.
6
71
CSTi
Control ST-BUS Input. CSTi carries serial streams for CAS and CCS respectively
a 2.048 Mbit/s ST-BUS control stream which contains the 30 transmit signalling
nibbles (ABCDXXXX or XXXXABCD) when RPSIG=0. When RPSIG=1 this pin
has no function. The most significant nibbles of each ST-BUS time slot are valid
and the least significant nibbles of each ST-BUS time slot are ignored when control
bit MSN (page 01H, address 1AH, bit 1) is set to 1. If MSN=0, the position of the
valid and ignored nibbles is reversed.
7
8
9
72
73
74
DSTo
DSTi
Data ST-BUS Output. A 2.048 Mbit/s serial stream which contains the 24/30
PCM(T1/E1) or data channels received on the PCM 24/30 (T1/E1) line.
Data ST-BUS Input. A 2.048 Mbit/s serial stream which contains the 24/30 (T1/
E1)PCM or data channels to be transmitted on the PCM 24/30 (T1/E1)line.
DS/RD
Data/Read Strobe (Input).
In Motorola mode (DS), this input is the active low data strobe of the
microprocessor interface.
In Intel mode (RD), this input is the active low read strobe of the microprocessor
interface.
10
11
12
83
84
CS
Chip Select (Input). This active low input enables the non-multiplexed parallel
microprocessor interface of the MT9074. When CS is set to high, the
microprocessor interface is idle and all bus I/O pins will be in a high impedance
state.
RESET
IRQ
RESET (Input). This active low input puts the MT9074 in a reset condition. RESET
should be set to high for normal operation. The MT9074 should be reset after
power-up. The RESET pin must be held low for a minimum of 1µsec. to reset the
device properly.
85
Interrupt Request (Output). A low on this output pin indicates that an interrupt
request is presented. IRQ is an open drain output that should be connected to VDD
through a pull-up resistor. An active low CS signal is not required for this pin to
function.
13 -
16
86-89
D0 - D3
Data 0 to Data 3 (Three-state I/O). These signals combined with D4-D7 form the
bidirectional data bus of the microprocessor interface (D0 is the least significant
bit).
3
MITEL [ MITEL NETWORKS CORPORATION ]
