Sony Ericsson GR47/GR48 User Manual

Page 75

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14. USING THE DEVELOPER’S KIT

75

LZT 123 7589 R1A

DIS

-

When fitted, the serial port driver IC disables the

receiver buffers that normally drive UART signals into

the radio device. This will prevent the radio device

from receiving data through the serial port.

WAKE

-

When fitted, the radio device will automatically

power-up when the UART DTR signal is driven high.

This allows a convenient mechanism for an external

host computer to switch on the module. The DTR

signal must be driven low or negative before the

module can be switched off under software

command.

Note: If DTR is not driven low or negative and the host

computer commands the module to shut-down, the

DTR signal in its high state will immediately indicate

that the module is to switch back on.

BAUD

-

When fitted, this jumper allows the serial port driver IC

to operate at baud rates in excess of 250 kbps and

up to 1 Mbps.

Note: There will be an increase in current

consumption with this option selected.

SHDN

-

When fitted, the serial port IC is forced into a low

power state with the internal transmitters disabled. In

the shut-down state the radio device will still receive

commands but any transmission attempts from the

radio device will be blocked by the serial port IC.

Notes:

In the shut-down state all the hardware flow control

transmitters will be switched off. In order to send

commands to the radio device in this state, the host

computer must also have hardware flow control

switched off.

There is a second jumper labelled ’SHDN’ which is in

the Power Supply area (adjacent to U7).

Jumper

Default

Description

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