ima newbie with TLP/RLP TX/RX with HT12d/e decoders/encoders

Wireless & IoT
1

Hey guys, I’ve done abit of reading on the site to try and find out an answer to my question, but alot of it goes too deep for me… Im 22, avionics technician, and can handle abit of techo lingo, my problem appears to be from the reciever side of things.

I have a 16f84 simply incrementing a 4 bit word and then setting a pin low for one cycle to enable TX from the ht12e, then allowing 1/100 of a second(should be lots of time for a 3Kosc set on the ht12e/d to send one word).

However… always a however for my projects… the ht12d recieves data here and there - the first few words are right on the ball, then it appears like the decoder gets out of synch… bad juju…

The data is TX/ing fine, i have a LED on the signal out line to the RF tx’er(TLP 433Mhz) and its flashing away doing its thang, but the ht12d on the RX is not getting the data… I have a LED on the data line from the RLP on the receiver and there appears to be alot of noise when the TX isnt even transmitting, on that I tried moving the board around the house to see if it was jsut the room i was in, but it wasnt. The LED flashes dimmly with no TX, I would have thought that it would stay off(0v) with no data being recieved…

Anyhow, one last thing, even though the data is being sent at around 3K as definned by the RLP/TLP and ht12d/e Fosc settings, why is it that i cant seem to get data transfer nealry as fast, is the 3K bits per second or bytes per second?

Thanks in advance guys, after reading some of the other forums out there its really got me thinking about new projects and designs, but hey, gotta start somewhere :wink:

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one other thing i forgot to menchin, is that continually sending data works fine… no matter what the word is, but when i change the data to be sent(stop tx’ing, change the word, and enable it again - hence the 4 bit incrementing word from the pic) the decoder just cant handle it, its sending fine, but the decoder will get maybe one or 2 transmissions every 10 seconds… the data is deffinetly being recieved via indication of the LED on the data line from the RLP to the ht12d, but not decoding it… the data lines are both tied to earth with a 10K resistor aswell.

3

well, after endless hours over the last week of delving deeper into the world of RF, i learnt a few things…

you guys take for ever to respond lol

baud aka bits per second or rate of signal change per second is not bytes per second…

picbasic hauls ass… alot of ass. I was a big fan of assembly code with the picmicros, and enjoyed the challange of developing programs to interface with new components like lcd screens/keypads/eeproms, but after affiliating with picbasic (crownhill proton picbasic pro) i’ll never look back.

serial data sent at 9600 baud with the simple command

SEROUT PORTA.0 , T9600, [“AZ”, dec variablex,“M”]

how easy is that… although the RF modules that i have only support 3k baud, you just change the t9600 to t2400 to modify the baud rate, and presto, when hooked up to your RF module, its serial data transfer without anything in between. and its completly compatable for pc interfacing and data transfer… zomg the possibilities…

the serout command can be used on pics without serial data transfer like uart/i2c, is pre compiled code that its compiled to assembly, but simply programmed with basic… love it… its like the visual basic if pic programming…

sending data to lcd screens is simple

print at 1,1, "A: ", dec vasriableA, " B: ", dec variableB

and matrix keypad scanning:

keypad_entry = INKEY

damn thats sweet, all the lcd initialisation is carried out in the assembly code and not to be worried about. that said you can still modify all the lcd parameters if you want to have your cursur shown for example… all the wiring diagrams can be found riddle throughout the help file, and the search index gets you places fast.

sorry to blabble on, im the biggest newb at all this, just that picbasic pro is out of this world and im getting it off my chest lol.

ht12d/e encoders really suck… they cant handle data transfer all that well, and are slow in comparison too what i have been experimenting with on the pic’s