User Guide

Issue 1 12/04 COMPANY CONFIDENTIAL 35

RAE-6/RA-4

6 - Baseband Description and Troubleshooting Nokia Customer Care

■ CMT keypad

The amount of keys in RAE-6/RA-4 on the lid side is 27. The keys are connected to the

OMAP1510 keyboard interface, except the power key, which is connected to PWRONX pin of

UEMEK. Keyboard interface in OMAP1510 has a 6x5 matrix. The total amount of the keypad

signals through hinge flex is 12. Keyboard matrix can be seen in Table 9, “Keypad placement

matrix.” Keys are divided into CMT keys and CBA Soft Command keys that are also called PDA

keys. CMT keys are on the topside of the lid and PDA keys are on the bottom side, next to the

PDA display. All the signals go through EMI filters.

Table 9: Keypad placement matrix.

Table 10: OMAP1510 keypad interface

Description of operation

A keyboard Interface in OMAP1510 consists of specific I/O pins, dedicated for the 6 columns

X 5 rows keyboard connection.

The keyboard interface is composed of six column lines (output), KBC (5:0); and five row lines

(input), KBR (4:0) with the capability to detect multiple key pressing.

When no key is pressed, KBD_INT remains high because of external pull up, once key(s) is

(are) pressed, the corresponding row(s) and column(s) are shorted together, since KBC is set

to low initially, therefore, KBD_INT is changed to low state and interrupt is generated that CPU

will perform a scanning process to tell which key(s) are pressed.

In case of a determined key press SW must ensure is the key pressed or not by multi-read op-

eration.

Illumination and drivers

The illumination includes:

Col 0 Col 1 Col 2 Col 3 Col 4 Col 5

Row 0

Special key

UP CMT 1 CMT 2 CBA 1 CBA 2

Row 1

PUSH SEND END CBA 3 CBA 4

Row 2

DOWN 1 2 3 *

Row 3

LEFT 4 5 6 0

Row 4

RIGHT 7 8 9 #

From Signal Pin(s) To Signal Pin(s) Levels Description

OMAP1510 APE_KEYB(10:0) Keyboard

Matrix

Column(5:0) 0-2.8V Keyboard control:

Column

Keyboard

Matrix

Row (4:0) OMAP1510 APE_KEYB(10:0) 0-2.8V Keyboard control:

Row with external pull-