Tws 434/ Rws 434

[Jerson]

Try baud rate 1200 instead of 2400. Most of these modules are good at this frequency.

[mackrackit]

Two things:
First, the junk data transmitted has to be a certain type of junk. The receiver has to be put into a “middle” state in order to work. Think of a capacitor that is charged to its maximum of 25 volts. Adding a 25 volt signal to it will not have a change on its state. The same goes for one that is zero charged, 0 volts will not change its state. In order for either 0 or 25 volts to have the same effect the capacitor has to have an initial charge of 12.5 volts.

To put the receiver in a “middle” state send $55 five times. Then send the synch then your data all on one line.

'transmitted
junk = $55
synch = a
SEROUT PIN,N2400,[junk,junk,junk,junk,junk,synch, data]

'received
SERIN PIN, N2400,[“a”],data

Notice I used the SERIN/SEROUT , not SERIN2/SEROUT2.

[PJALM]

These modules require all data to be encoded using the Manchester code. Search this forum for it and you will find lots of examples.

[dhouston]

These modules require all data to be encoded using the Manchester code. Search this forum for it and you will find lots of examples.

Manchester encoding is not a requirement. They are used extensively without it.

[mackrackit]

Manchester encoding is not a requirement. They are used extensively without it.

Agreed. When I was having my problems with SERIAL, tested RF by simply sending a high bit.

Kind of like Morse code. Instead of "..._ _ _..." it was "... ..."
DOTS = HIGH

[jmbanales21485]

sorry for the late reply, i have not had time to work on this till now.


so it tried what you said and sent %10101010 to stabalize the oscillators, (put it in the neutral zone). and now i am able to get something on the other end of the pic. however i can't seem to get it continously. in my sample program i am counting numbers continously in my transmitter side and sending it to my reciever to display it. it sends numbers but it does not send it continously.

i.e i send 1,2,3,4,5,6,7,8,9,10 and will recieve 1, 4, 6,9

how do i make my program more stable.

'=====transmitter=====
junk = $55
synch = "a"
dat = 0
loopa:
pause 1000
serout tx, N2400, [junk, junk, junk, junk, junk, synch, dat]
dat = dat + 1
if dat = 255 then dat = 0
goto loopa

'=====reciever======
synch = "a"
dat = 0
begin:
serin rx, 4, [synch], dat
pause 5:serout2 LCD, baud, ["start", 1, DEC (dat), 0]
goto begin

[dhouston]

For small amounts of data I prefer using the NEC protocol which has been around since the dawn of remote control and has been widely used by manufacturers of audio/visual gear.

I posted a short example for sending/receiving in the Code Examples forum.

http://www.picbasic.co.uk/forum/showthread.php?t=6261