User Guide

RH-23 Company confidential

System Module and User Interface CCS Technical Documentation

Page 30 Nokia Corporation. Issue 1 02/2004

face is the same like other DCT4 projects. The vibra is controlled by a PWM signal from

the UEM

UI Board (Keyboard)

RH-23 has separate UI board, named as 1BF, which includes contacts for the keypad

domes and 4 LED’s for keypad lighting. 4 resistors beside each LED are for ESD purposes

and connected to GND from both ends. UI board is connected to main PWB through 20

pole board-to-board connector with springs.

Keyboard is Douglas 4 style and 6x5-matrix keyboard is for controlling the keyboard. Key

pressing is detected by scanning procedure. Keypad signals are connected UPP keyboard

interface.

When no key is pressed, row inputs are high due to UPP internal pull-up resistors. The

columns are written zero. When key is pressed one row is pulled down and an interrupt is

generated to MCU. After receiving interrupt, MCU starts scanning procedure. All columns

are first written high and then one column at the time is written down. All other col-

umns except one, which was written down, are set as inputs. Rows are read while col-

umn at the time is written down. If some row is down it indicates that key which is at

the cross point of selected column and row was pressed. After detecting pressed key all

Table 25: Keyboard (board-to-board) Connector

Pin Signal Note

1 GND Ground

2 ROW(4) Keyboard matrix row 4

3 ROW(3) Keyboard matrix row 3

4 COL(2) Keyboard matrix column 2

5 ROW(2) Keyboard matrix row 2

6 COL(1) Keyboard matrix column 1

7 ROW(0) Keyboard matrix row 0

8 ROW(1) Keyboard matrix row 1

9 COL(3) Keyboard matrix column 3

10 COL(4) Keyboard matrix column 4

11 GND Ground

12 ROW(5) Keyboard matrix row 5

13 GND Ground

14 VLED1+ Supply Voltage for Keyboard LED

15 VLED2+ Supply Voltage for Keyboard LED

16 VLED3+ Supply Voltage for Keyboard LED