I am trying to transmit a single byte of data wirelessly between two 16f88’s. I tried serin/serout code that works perfectly with a wire connection, but when I tried incorporating the RF link I did not get the same result. I tried using qualifiers in the code as well as serin2/serout2 as well as hserin/hserout all with the same dysfunctional result. any ideas to what I am doing wrong would be most helpful. using 2400 baud rate.
There are a number of threads on this forum that address this issue. Do a search on this forum for RLP-434 or browse the topics in the Wireless/RF section.
I have been looking alot at the other threads. I did find one useful bit of information that I tried with limited success. I inverted one of the baud rates. Right now I just have a two button, two led setup. At least now a LED comes on when I press a button. Not necessarily the right one; but it seems to be a step in the right direction. I tried putting qualifiers on the serin/serout and then the LEDs would not come on at all. When I changed the code so that different numbers were sent (higher ones…97 and 45) the LED’s did not come on nearly as much. any suggestions? I will keep looking at other threads.
ryanbeckett:
I tried putting qualifiers on the serin/serout and then the LEDs would not come on at all. When I changed the code so that different numbers were sent (higher ones…97 and 45) the LED’s did not come on nearly as much.
Could you tell us a little more about what data you’re sending over the link? An important thing to keep in mind about these devices is that the receivers require a short period of time to adjust to the incoming signal. They have an AGC (automatic gain control) circuit that adjusts the sensitivity of the receiver. This is why people send preamble bytes to allow the receive to come online. The other issue is that the digital output of the receiver will have sporatic output in the absence of a transmission from device. This can cause problems decoding the signal unless steps are taken to address that fact. I have had success adding a comparator driven by the output of the receiver (there are references on this forum – search for Luhan Monet, it was his idea). I also ran across a [squelch circuit which “mutes” the output of the receiver in the absence of a signal, accomplishing the same objective, but is slightly more involved.](http://www.linxtechnologies.com/linx-kb/?sid=82295&aktion=artikel&rubrik=001&id=73&lang=en)
does the RLP have RSSI? Mine doesn’t though I know there are a lot of similar models that do.
Philba:
does the RLP have RSSI? Mine doesn’t though I know there are a lot of similar models that do.
The analog output is the closest thing that could be considered a signal strength indicator on the RLP. I included the link as I thought it was interesting that Linx also saw the value of a squelch/threshold approach for some situations.
OK,
I checked out the squelch circuit and other comparator ideas. I guess what I’m trying to get at is there any “simple” way to make the tx/rx act as a “wire” just with some adjustment in the code? This may not be possible, but as there is a time crunch and getting this setup to work as soon as possible is desirable without having to buy extra chips. Your thoughts? Oh, and since the 16f88 does not have RSSI(I think), can I still use the squelch circuit?
Sorry, I should have defined RSSI (Receiver Signal Strength Indicator). It is a feature of the receiver to indicate the relative strength of an incoming signal, and not the 16F88.
As far as a software only approach goes, try out the sample code I provided in [this thread, and see if it works for you.
If it works, adapt the code to your needs. If it kinda of works, building a comparator like the one used in [Luhan’s Cricket receiver would be worthwhile. It consists of a dual op-amp, 3 resistors, and a diode. Pretty straight forward and easy to build. I use a circuit almost identical to his to reliably send data over 100’ using these transmitters and receivers.](http://members.cox.net/berniekm/crickr.gif)](http://www.sparkfun.com/cgi-bin/phpbb/viewtopic.php?t=4222&highlight=comparator)
All I really need is for 5 different LEDs to come on (5 different functions) with the five buttons with one connecting wire (RF link). Its a control scheme for RC submarine for a project in a mechatronics class.
Thank you…I posted that last one and apparently didn’t see your recent reply. I will try the code and I suspect I will want to try the comparator circuit as well.
Ok,
I am not very saavy at converting from proton+ to picbasic pro code. I did however try the squelch circuit which I am optimistic that it will work. However I have not gotten it to work yet with the picbasic code I had written from before. It would be extremely helpful if you could provide a couple lines of code(for tx and rx) in picbasic pro that could turn on a couple LEDS with the press of a button(s). Thanks
riden:
Philba:
does the RLP have RSSI? Mine doesn’t though I know there are a lot of similar models that do.The analog output is the closest thing that could be considered a signal strength indicator on the RLP. I included the link as I thought it was interesting that Linx also saw the value of a squelch/threshold approach for some situations.
The RLP has an analog output. I looked at the various receivers I have laying around, and 2 models have the “analog” output (pin 3) labeled as “RSSI”. I get the same type of output from all 3 of my receivers so I suspect the “analog output” and “RSSI” can be used interchangeably here. Of course, your mileage may vary. 
ryanbeckett:
Ok,I am not very saavy at converting from proton+ to picbasic pro code. I did however try the squelch circuit which I am optimistic that it will work. However I have not gotten it to work yet with the picbasic code I had written from before. It would be extremely helpful if you could provide a couple lines of code(for tx and rx) in picbasic pro that could turn on a couple LEDS with the press of a button(s). Thanks
PICBasic and Proton are very close as Proton was designed to be PICBasic friendly. I haven’t experienced any problems converting from one to another. In any case, what part of the code are you having trouble converting? When you type in the example code, what error messages are you receiving from PICBasic?