MT9171/72

Data Sheet

8

Zarlink Semiconductor Inc.

extracted and the Receive Interface separates the channels and outputs them to the proper ports in the proper

channel times. The destination of the various channels is the same as that received on the input DV and CD ports.

The Transmit/Receive Timing and Control block generates all the clocks for the transmit and receive functions and

controls the entire chip according to the control register. In order that more than one DNIC may be connected to the

same DV and CD ports an F0o signal is generated which signals the next device in a daisy chain that its channel

times are now active. In this arrangement only the first DNIC in the chain receives the system F0 with the following

devices receiving its predecessor’s F0o.

In MOD mode, all the ports have a different format. The line port again operates at 80 or 160 kbit/s, however, there

is no synchronization overhead, only transparent data. The DV and CD ports carry serial data at 80 or 160 kbit/s

with the DV port transferring all the data for the line and the CD port carrying the C-channel only. In this mode the

transfer of data at both ports is synchronized to the TCK and RCK clocks for transmit and receive data, respectively.

The CLD signal goes low to indicate the start of the C-channel data on the CD port. It is used to load and latch the

input and output C-channel but has no relationship to the data on the DV port.

Operating Modes (MS0-2)

The logic levels present on the mode select pins MS0, MS1 and MS2 program the DNIC for different operating

modes and configure the DV and CD ports accordingly. Table 1 shows the modes corresponding to the state of

MS0-2. These pins select the DNIC to operate as a MASTER or SLAVE, in DUAL or SINGLE port operation, in

MODEM or DIGITAL NETWORK mode and the order of the C and D channels on the CD port. Table 2 provides a

description of each mode and Table 3 gives a pin configuration according to the mode selected for all pins that have

variable functions. These functions vary depending on whether it is in MAS or SLV, and whether DN or MOD mode

is used.

Table 1 - Mode Select Pins

E=Enabled

X=Not Applicable

Blanks are disabled

Mode Select Pins

Mode

Operating Mode

MS2

MS1

MS0

SLV

MAS

DUAL

SINGL

MO

D

DN

D-C

C-D

ODE

00

0

0

E

E

E

E

E

00

1

1

E

E

E

X

X

E

01

0

2

E

E

E

E

E

01

1

3

E

E

E

E

E

10

0

4

E

E

E

E

E

10

1

5

E

E

E

X

X

E

11

0

6

E

E

E

E

E

11

1

7

E

E

E

E