NSW-5
System Module UT5U
PAMS Technical Documentation
Page 29
Issue 1 10/00
Nokia Mobile Phones Ltd.
infrared light from and to electrical data pulses running in the two wire
asyncronous databus. IR databus is the same as used for FBUS data
transferring. Thus FBUS Tx and Rx lines must be turned to IR mode. The
IR mode can be selected from user interface.
The module is activated with the IRDAEN signal by MAD, which supplies
power to the IR module (N350) and enables supply current for IR leds.
The IR datalines are connected to MAD accessory interface AccIf via
FBUS. The RX and TX lines are separated from FBUS by 3–state buffer
(D350), when the IR–module is switched off. The AccIf performs pulse
encoding and shaping for transmitted data and detection and decoding
for received data pulses.
The data is transferred over IR link using serial FBUS data at speeds 9.6,
19.2, 38.4, 56.6 or 115.2 kbits/s, which leads to maximum troughput of
92.160 kbits/s. The used IR module complies with the IrDA SIR specifica-
tion (Infra Red Data Association).
Following figure gives an example of IR transmission pulses. In IR trans-
mission a light pulse correspondes to 0–bit and a ”dark pulse” corre-
spondes to 1–bit.
UART TX
IR TX
startbit
stopbit
1
0
1
0
0
1
1
0
constant pulse
The FBUS cannot be used for external accessory communication, when
the infrared mode is selected. Infrared communication reserves the FBUS
completely.
User Interface
The Display Module is connected to engine board via X300. It contains
LCD and LCD LEDs, power switch, and speaker pads.
TM23A (N300), a.k.a. UISWITCH, is an integrated switch IC for UI pur-
poses. It includes control switch for buzzer and vibra, LED (display & key-
board) control and two current sinks for LEDs.
