FEDL9478C-01

ML9478C

14/31

DESCRIPTION

Operation description (Serial interface)

• Display data input

As described in the Data configuration section, the display data consists of the data field that corresponds to

each segment on/off and the command field that indicates the display data input.

When inputting the display data, the "F3" command is set in the command field.

When the "F1" or "F2"

command is set in the command field, the display data in the data field becomes invalid.

The data input to the DATA pin is loaded to the shift register at the CLOCK pulse rise, transferred to the

display data latch during the LOAD pulse at the "H" level, then output via the segment driver.

D1

D2

D3

D4

D80 C0

C1

C2

C3

C4

C5

C6

CLOCK

DATA

New data

LOAD

Display output

C7

Data field

Old data

Command field

• Display on, Display off

The display becomes off at power-on reset. To display, write the display on command.

The display off is the command that makes all segments off. Writing the display off command turns off the

lights regardless of the display data.

The display on is the command to release the display off. Writing the display on command returns the display

to the original state.

D1 D2

C6

C4 C5 C6 C7

C4 C5 C6 C7

CLOCK

DATA

LOAD

Display ON/OFF

C7

RESET

Display data input

Display on

command write

Display off

command write