Pin Name

I/O

Internal

connection

Description

R

M

L

IPull-Low

Three key-switches have seven different combinations in total.

Both key-pressed and key-released signals will be sent

accompanied with horizontal and vertical state. The status of

the key-switches, the values of horizontal or vertical counters

will be present at RXD and RXD. The debounce interval for

both key-press and key-release is 13ms.

X1

X2

Y1

Y2

I—

Four photo-couplers signals denote UP, DOWN, LEFT, and

RIGHT state.

During the scaning period, as long as the photo-couplers

change their states, the value of vertical or horizontal counter

will increase or decrease accordingly.

VDD

I

—

Position power supply

Approximate Internal connection circuits

HT6513

3

23rd Oct ’96