Information word

If L/MB=1 the device is in the latch mode (for use with the latch type of data decoders). When the trans-

mission enable is removed during a transmission, the DOUT pin outputs a complete word and then

stops. On the other hand, if L/MB=0 the device is in the momentary mode (for use with the momentary

type of data decoders). When the transmission enable is removed during a transmission, the DOUT

outputs a complete word and then adds 7 words all with the ²1² data code.

An information word consists of 4 periods as illustrated below.

Address/data waveform

Each programmable address/data pin can be externally set to one of the following two logic states as

shown below.

HT12A/HT12E

1/ 3 bi t s y n c . per i o d

pi l o t pe r i od ( 12 bi t s )

addr es s c ode per i o d

per i od

dat a c ode

Composition of information

"O n e "

" Z er o"

f OS C

A ddr es s /

Da t a B i t

Address/Data bit waveform for the HT12E

"O n e "

" Z er o"

f OS C

Da t a B i t

Da t a B i t

"O n e "

" Z er o"

A ddr es s B i t

A ddr es s B i t

38k H z

ca r r i e r

Address/Data bit waveform for the HT12A