MT8982AC datasheet(7/14 Pages) MITEL

7 / 14 page

ISO-CMOS

MT8982

2-37

Write Connect Memory - Set Connection Mode

(Cmd0-1: 0,1)

The

corresponding

output

channel

the

addressed

Connect

Memory

location

conﬁgured in connection mode. The Connection

Mode Data Byte (Table 2) will be received by the

MT8982 in the following data byte. Bits 0 to 4

(SC0-SC4) select the source input channel for

switching to this output channel.

Bit 5 (STi)

selects the input stream. Bit 6 (ODE) enables/

disables tristate for this channel. Bit 7 is unused

in connection mode.

Read Data Memory (Cmd0-1: 1,0)

The contents of the addressed Data Memory

location are transmitted to the microcontroller in

the following data byte.

Write Connect Memory - Set Message Mode

(Cmd0-1: 1,1)

The

corresponding

output

channel

the

addressed

Connect

Memory

location

conﬁgured in message mode. The following data

byte will be received by the MT8982 and written

to the address Connect Memory location.

The

data

byte

will

output

directly

the

corresponding output channel.

The following example shows a typical programming

sequence for the MT8982. A connection is to be

made from stream 1 channel 6 to stream 0 channel

15:

•

The microcontroller pulls CS low.

•

The microcontroller transmits eight clock pulses

to SCLK and a Command/Address byte, HEX

3E, to RxD.

The Command/Address byte

addresses

output

channel

15,

stream

conﬁgures that channel as connection mode

and identiﬁes the microcycle as a write to the

Connect Memory.

•

The microcontroller transmits another eight

clock

pulses

SCLK

and

sends

the

Connection Mode Data Byte, HEX 26, to RxD.

The Connection Mode Data Byte addresses

input channel 6, stream 1 in the Data Memory.

Note that at least two microseconds must occur

between the two accesses.

The

connection

now

complete.

The

microcontroller may now check that the connection is

correct:

•

The microcontroller transmits eight clock pulses

to SCLK and a Command/Address byte, HEX

3C, to RxD.

The Command/Address byte

addresses output channel 15, stream 0 and

identiﬁes the microcycle as a read from the

Connect Memory.

•

The microcontroller transmits another eight

clock pulses to SCLK. The MT8982 outputs the

Connect Memory data, HEX 26, on TxD.

least two microseconds must occur between

the two accesses to ensure that the MiniDX can

clock out the data.

•

CS goes high to terminate the session.

This connection is only in one direction. To make a

bidirectional connection the MT8982 must also be

programmed to connect stream 0 channel 15 to

stream 1 channel 6.

Serial Bus Mode

When the microport is in serial bus mode the

MT8982 is programmed via the two ST-BUS serial

streams CSTi0 and CSTi1. Each channel in these

two streams is written directly into the corresponding

address in the Connect Memory. The data written to

the Connect Memory is always the Connection Mode

Data Byte as described in Table 2.

To set up a

connection, the Connection Mode Data Byte is

transmitted to the MT8982 on the CSTi stream and

channel number which is the same as the desired

STo stream and channel number.

As long as the

device remains in serial bus mode, the Connection

Mode Data byte must be transmitted continuously,

every frame, to maintain the connection.

Message mode is not available when the device is in

serial bus mode. Also, neither the Connect Memory

nor the Data Memory can be read while the device is

in serial bus mode.

MITEL’s MT8980, MT9080 and

MT8920 devices can all be used as programmable

parallel-to-ST-BUS serial interfaces for CSTi0 and

CSTi1.

Initialization

On power up the contents of the Connect Memory

can be in any state.

In order to prevent false

programming of peripheral ST-BUS devices or false

data transmission, ODE should be kept low during

power up. This will keep the two TDM outputs in high

impedance until the MT8982 Connect Memory is

programmed.

MT8982AC 데이터시트(PDF) 7 Page - Mitel Networks Corporation

MT8982AC 데이터시트(HTML) 7 Page - Mitel Networks Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14

데이터시트 다운로드

링크 URL