MSM6606 Ver la hoja de datos (PDF) - Oki Electric Industry

Número de pieza

componentes Descripción

Fabricante

MSM6606

80-DOT LCD DRIVER WITH KEY MATRIX

Oki Electric Industry 

¡ Semiconductor

FEDL6606-03

MSM6606

• Keyscan

Keyscan starts when the key status has changed, or when the "Key Scan Start" command has

been written. Scan continues until the "Key Scan Stop" command is written. (Scan stops

when a reset signal is applied.)

When 1 keyscan cycle (TSCN) ends, the INT signal becomes "H", so this signal can be used as

an interrupt flag, which is dependent on switcing conditions of keys. The INT signal is reset

when either the LOAD pulse is input after the key data is output, when the "Key Scan Stop"

command is set, or when a reset signal is applied.

TSCN

R0

R1

R2

R3

R4

INT

Key Scan Start Command Write,

or Key Status Changed

Data Read

Key Scan Stop Command Write

Notes:

1. A recognition error (a switch that was actually not pressed is recognized as

having been pressed) may occur if 3 or more key switches are pressed at the

same time. If simultaneous pressing of 3 or more key switches needs recognizing,

serially insert diodes into each switch. If pressing 3 or more key switches at the

same time is not allowed, a possible software approach is to ignore the read data

when there are 3 or more 1s in the key data.

2. A change of key status is detected as a change of column inputs (C0 - C5).

Therefore if multiple switches which are connected to the same column are

pressed at the same time, a change of key status will not be detected.

12/18

Share Link: