µPD6121, 6122

11

18 ms to 36 ms

3

27 ms

4.5 ms

9 ms

13.5 ms

Leader Code

Custom Code

8 bits

Custom Code’

8 bits

Data Code

8 bits

Data Code

8 bits

Stop Bit

1 bit

58.5 ms to 76.5 ms

REM output

4.

REMOTE OUTPUT WAVEFORM (NEC TRANSMISSION FORMAT:

ONE-SHOT COMMAND TRANSMISSION MODE)

•

When fOSC = 455 kHz

(1) Remote (REM) output (from stage 2 , transmission occurs only when key is kept depressed)

(2) Magnification of stage 1

(3) Magnification of waveform 3

(4) Magnification of waveform 2

(5) Carrier waveform (Magnification of HIGH period of codes)

Remark

If a key is kept depressed, the second and subsequent times, only the leader code and the stop

bit are transmitted, which allows power savings for the infrared-emitting diode. If a command is

issued continuously in the same way the second and subsequent times as the first time, refer to

7. ONE-SHOT/CONTINUOUS COMMAND TRANSMISSION MODE.

1.125 ms

9 ms

13.5 ms

4.5 ms

0.56 ms

2.25 ms

01

1

0

0

REM output

58.5 to 76.5 ms

108 ms

108 ms

1

2

REM output

9 ms

11.25 ms

2.25 ms

Leader Code

0.56 ms

Stop Bit

REM output

REM output

9 ms or 0.56 ms

Carrier frequency: fc = fosc/12 = 38 kHz

8.77 µs

26.3 µs