nec ir protocol

[fisyon]

hi
i am using 16f877a @ 20 mhz.
i need a keypad input but i don't want to use a lot of pins. i thought i can use a tv remote and made a receiver by using ua741 & ir photodiode.
then i implemented Thomas Henry's SonyRemote example.
the program worked but it shows different results for same buttons. i tried 6+ remotes which i found in the home and i think none of them have sony protocol.
i found a freeware for testing remote protocols by using pc's sound card and it says "Nec" for all these remotes. ( http://www.ostan.cz/IR_protocol_analyzer/ )

how can i use a (NEC) remote?

[Anobium]

Have a look at this: http://sourceforge.net/p/gcbasic/discussion/629990/thread/9f266cd0/#c98f

Post a message to see if they can help.

Anobium

[fisyon]

@Anobium thank you.
i changed photodiode&741 with 3 pin ir receiver thing at first.
then i wrote a sub that can show the raw data.
this sub is triggered by external input (PortB.0 for 16f877a)
i hope this will help for people looking for a NEC(?) decoder.

sub irread
dim row1 as string
dim row2 as string
tick_on=0
tick_off=0
totalbits=0
bitontime=0
bitofftime=0
caperror=false
row1=""
row2=""
cls

do while irdetect =1 and tick_on<80
tick_on+=1
wait 100 us
loop

if tick_on<60 and tick_on>75 then caperror=true
do while irdetect =0 and tick_off<45
tick_off+=1
wait 100 us
loop

if tick_off<30 and tick_off>45 then
caperror=true
exit sub
end if

if caperror=true then exit sub

for countbits=1 to 32
bitontime=0
bitofftime=0
do while irdetect=1 and bitontime <255
bitontime+=1
wait 10 us
loop

do while irdetect=0 and bitofftime<255
bitofftime+=1
wait 10 us
loop

pulsetotal=bitontime+bitofftime

if bitontime>0 and bitontime<127 and bitofftime>0 and bitofftime<127 then
if pulsetotal>=100 then

  if countbits<=16 then
        row1=row1+"1"
     else
        row2=row2+"1"
     end if
  else
     bitvalue=0
     if countbits<=16 then
        row1=row1+"0"
     else
        row2=row2+"0"
     end if
  end if

else
if countbits<=16 then
row1=row1+"e"
else
row2=row2+"e"
end if

end if

next countbits
print row1
locate 1,0
print row2
wait 3 s

end sub

However i need to convert these bits to a byte or word variable. What is the best option for this?

[Anobium]

You can assign your incoming bits to the correct bit in a byte or word

dim incomingdata as word

    incomingdata.15= readyourvaluefromsensor 
    incomingdata.14= readyourvaluefromsensor
....
    incomingdata.0= readyourvaluefromsensor 

Anobium

[fisyon]

i tried your example but not works.
i can assign bit values to the elements of defined array of a byte variable.
that works but i have 32 bits total and that consumes 32 of bytes...

[Anobium]

Can I clarify.

You have an incoming data stream of 32 bits and you need to save this stream? Yes?

[fisyon]

yes, i have 32 bit data stream but i have to split it 16bit & 16bit variables

[Anobium]

Why do you have to split?

[fisyon]

first 16 bits of the stream carries adress data (device type)
and last 16 bits for button (command) data.
actually even last 16 bits are enough at the moment.
when i press a button i can see the stream on the lcd. that stream differs by which button pressed.
but then i got same vaule (ie 8) when i try to change a variable bit by bit as in your example.
example:

1011001001001101 'bit stream of a button 
0011100011000111 'bit stream of another button

i got "8" for all bitstreams at assigning them into a word variable

[Anobium]

Try something like. This is intended to read the 32 bit into one variable. I have not tested but something like this should work for you.

dim datastream as long

repeat 32
datastream.0 = readdatatreamin
rotate datastream left
end repeat

[fisyon]

YES!
thanks a lot :D

[alvaro javier villegas]

Good morning, I use the google translator, someone can write an example of how to use the library "REMOTE" in nec protocol.

Thank you

[bed]

please make a new thread and / or point us to the correct point of Lib
(http://gcbasic.sourceforge.net/help/_infrared_remote.html for example.)