Rev. 1.00

7

May 07, 2012

HT62104

Overlapped Key Input Transmission

Whentwokeyinputtriggerpulsesoverlap,thetimewherethesecondtriggerpulseoccurswilldeterminewhat

framecodewillbeoutputontheDOUTpin.Ifthesecondtriggerpulseoccursduringthegaptime,thefollowing

framecodewillbeoutputontheDOUTpinandwillbeacombinationofthetwotriggeredframecodes.The

followingdiagramshowsthetransmissionwaveform.

K1

K2

IRC

LED

DOUT

K1+K2

K1+K2K1+K2

K1

K1

K2

K2

K2

f

OSC

=455 kHz

Gap Time

FC 1: Key 1 Frame Code.

FC 2: Key 2 Frame Code.

FC 1+ FC 2: Combination of Key1 and

Key 2 Frame Codes .

Overlapping Key Inputs Occurring During the Gap Time

Ifthesecondavailabletriggerpulseoccursduringtheframecodetransmissionduration,thepresentframecode

beingtransmittedwillstillbeoutputontheDOUTpin.Herethecombinationofthetwotriggeredframecodeswill

beconsecutivelyoutput.Thefollowingdiagramindicatesthetransmissionwaveform.

K1

K2

IRC

LED

DOUT

K1+K2K1+K2

K1

K1

K2

K2

f

OSC

=455 kHz

Gap Time

FC 1: Key 1 Frame Code.

FC 2: Key 2 Frame Code.

FC 1+ FC 2: Combination of Key1 and

Key 2 Frame Codes.

K1

K1+K2

Overlapping Key Inputs Occurring During a Frame Code Transmission

Thesamemethodologycanbeappliedontherisingtransitionofanyavailabletriggerpulsestoseehowtheframe

codechangeswhenoverlappingkeyinputsoccur.