Radio TX and RX code

[mikedownunder]

Hi Steve

I have just sent you a PM if you can have a look.

I do not use any transistors. I have based my units on a previous working project using the same TX & RX units and that is still running OK, but I don't receive every message sent. Perhaps this is where I could be going wrong.

I have asked for a schematic to be emailed to me if that is at all possible.

I really am beginning to think that I have a hardware issue as both yourself and Barak have had huge successes with the software, and is Tim's after all

I will be checking my emails but we are now in the evening here it's getting dark already (even with daylight saving). If I don't have time tonight then hopefully I can have a crack tomorrow.

Thanks for the help guys.

Mike

[roger]

Originally Posted by Tim

Wow I was not expecting that kind of in depth analysis.

Now on to build in the ability to alter the bit rate then a few example applications and to release it.

Thanks again

Hi Tim,

I know you are busy, but could you advise whether I should continue to develop my radio link with your V1 software, which I have, V2, which I don't have, or will any work I do be superceded by your comment above, which I presume will include the 18 series TX mod?

Thanks

roger

[Tim]

Hi Roger

Sorry I seem to have got my self confused whether I was going to do an 18 series version.

I'm still not sure but sent you version 2 any case.

BTW I have not applied the amendment (see above) to it as I just forward a previous mail directly on. Please correct the variable name your end

If anyone else is still waiting please remind me.

[roger]

Tim,

Thanks very much.

Re 18F version, don't spend time doing this on my account, i will use the 16F as is.

roger

[mikedownunder]

Well guys I've got it going at last.

The problem was with my TX & RX units.
I bit the bullet and went out and bought a new pair from Jaycar this morning.
Plugged 'em in and up it all came.

I guess the problem was that my units are about a year old and have probably gone a bit off sync. They were OK with my old project because I was running it at 300 baud and I guess Tims is a lot faster.

Anyway I'm off and running and thanks for all of the help and assistance. Yet again the good ol forum does wonders.

Mike

[ta1dr]

sorry my USB memory device was damaged and no turn life could you send me stabl rx and tx code if you send PM I will send my email address
thanks for
ahmet

[leisryan]

Originally Posted by Tim

Hi Roger

Sorry I seem to have got my self confused whether I was going to do an 18 series version.

I'm still not sure but sent you version 2 any case.

BTW I have not applied the amendment (see above) to it as I just forward a previous mail directly on. Please correct the variable name your end

If anyone else is still waiting please remind me.

Sir:
I'd like to test and play around with your TxRx latest code, Can I request for it?

[Tim]

Pm me your mail address and I will send it to you

[SimonTempler]

Hi Tim,

Sounds like some interesting code, any chance I could have them too?

[Tim]

You need to PM me with your e-mail address.............

[hoyungh]

Tim could you please send me a copy? Thanks

[Tim]

It seems I have been sending out old versions of my RF code

I will resend it once I'm happy its the right one to all in my records I sent it to. However I do not have a complete record ...

If you have not got the new code in a couple of days please contact me

[hoyungh]

Could someone please give some guidelines on how to connect those cheap ASK modules. I have used a stripboard and think I have run into a wall. At first I used a 13 inch wire as an antenna. With version1 of Tim's code I didn't get a result. As suggested in this thread I placed an led on the input of the pic of the receiver and saw the three flashes but no output from the pic.
With SYBLIN_VCob the counter updated but missed counts. I have since made a 4 element Yagi antenna and things have improved dramatically but I still gets missed counts. I have arranged to flash an led everytime the program called on SYBLIN_Cob and noticed it doesn't always flash when the input flashes. Sometimes it fails to flash at all for 3 or 4 counts.despite having an antenna thats supposed to extend the range above 250 ft.

[Tim]

I have to point out that the code I was sending out was correct but it was not the easiest to use. The later version did the CRC stuff automatically

The original code you sent me would not even compile

Its been a long time since I used AM devices so I cannot help especially on those modules

[hoyungh]

Sorry Tim. Obviously I wasn't clear. I think its a layout issue but googling hasn't given me an answer. Putting the stuff in a metal box appeared to help. Somewhere in this thread Barack mentioned loss of 0.75% but I am getting 5% now but I don't know what works and what doesn't hence the request for guidelines.
In audio work its star point grounding, bypassing ic's with 0.1 uF caps, twisted pair for low signal wires but that doesn't appear to work here.
Sorry if my previous post hurt your feelings. The fault and errors are all mine.

[chuckieboy]

I soldered mine modules into a strip board and and used flying leads to pulg into the Proton development board and just used a 17" long wire fo the aerial and I have got a very good range about 200 mteres. even took it to work where there is lots of Metal and other electronic stuff and it worked well the range was reduced but it sill worked well.
These are the FM modules from RF solutions.

Try soldering the modules into stripboard and make sure the antenna wire is soldered has cloase to the pin has possible, I think I've got some cheap AM TX/RX that was part of another system, If I get time I'll dig them out and hook them up and see how I get on thia side with them

[Tim]

For the purpose of the tests you should solder the right length aerial directly to the TX/RX pin on the module

you can get so many loses due to the solder connection is amazing

[barak]

Hoyungh,
I doubt if your problem is layout or assembly related. While RF circuit are very sensitive to layout, soldering etc., ASK modules, are build on a hybrid circuit which takes care of all the layout and small signal issues. In my experience, as long as the antenna is connected directly to ANT pin, they don’t require any special assembly considerations.
In the tests that I reported on this thread, I prototyped on solderless breadboards. I used circuits from Princeton PT4450/RX3400 and also from another unknown maker TWS-434 , RWS-434 (http://www.rentron.com/remote_control/RWS-434.htm). Nominally, the antenna should be ~17.5 cm but to reduce the sensitivity, I used 3cm or no antenna at all and it still worked two rooms across. Even in commercial products that work up to 200 meters I sometimes plug the module into a simple female header, so it is easy to replace, and don’t see significant change in range compared to a soldered module.

If you just want to check that your hardware is OK, I recently posted on another thread a simple code example that I used to verify the circuits before testing more complex code. See http://www.picbasic.org/forum/showpo...12&postcount=3

Always use crystals on both ends and until everything works OK, not more than 2400bps.
Also, sometimes these modules don’t work well when the RX is too close to the TX (under 2 meters), so until you got everything else going, I would test at 4 meters apart.

[hoyungh]

Thank you all for your replies. I got my rf units from Blitzlogic and they have a trimmer on the receiver and it must have moved while in transport.
After having wildly fluctuating results I decided to adjust the trimmer and fortunately found a position where the led I arranged to flash everytime the program called on SYBLIN_Cob appeared to flash in time with the flash from the module output. I still cannot get 3 flashes every time but even two flashes appears to update the count and I don't appear to have anymore missed counts.
I suppose the lesson is not to buy units that have adjustable parts.
Thank you again for for your help.

[CharlieBrown]

Needless to say , how helpful , Tim's code was to me, I made my self a small RF test Jig, who's photograph is attached to this reply.

Some points to note -
1. Both , the receiver and Transmitter are on the same board.
2. Power to the Rx / Tx are switched on/off with Jumper pins provided.
3. LED indications of the Data being transmitted, Receiver pin level and programmed output from the MCU.
4. RS232 In/Out.
5. 20 Mhz Clock
6. Provision of a 4 way dip switch , function not yet programmed or decided.
7. Tested the setup with 16F676.

I also share the schematic , if anyone's interested. Sorry , its a pdf file.

regards.

[chuckieboy]

Looks good, I take it you have 2 boards one set up for RX and the other TX ?

I was going to layout a board for testing, but in the end I just used the dev boards I've got, In seeing your test rig has inspired me to get the cob webs of my drawings again.

This will save me keep swapiong dev boards for other projects

[CharlieBrown]

Actually , I made this to monitor or debug data being communicated between the Rx/Tx of a Remote control unit. The idea at first was just to build a RF Rx to send data to the RS232, but then , instead of wasting pins of the MCU, I added the Tx part also. I have only managed to put the RF part on the test jig to use. Did not feel the need to use the Tx part as yet.

Some more photographs of a simple RF Rx and Tx that I made.

I wonder if I could merge both the codes into one and then use the DIP switches to select a function.

Wonder if TIM got any further in getting those macro/command made.

[chuckieboy]

Charlie it may be possible Tim would be the best person to answer this one,
I'm not sure if using the 2 include files in the same code would casue a conflict with each other, It would be interesting to know, This then would make a cool encoder/decoder chip.
This code I found was for PBP but I converted to PDS

'// Test for encode or decode function & configure I/O
  DelayMS 10            '// Stabilize on power-up
  If PORTA.6 = 1 Then '// Is Decode MODE selected..?
      PORTB = 0          '// All outputs = 0 (off)
   TRISB = 0          '// PORTB all outputs (8-bit data output)
   OPTION_REG.7 = 1   '// PORTB pull-ups off
   GoTo Decode        '// GOTO Decode routine
  EndIf               '// Else encode function selected
  TRISB = $FF         '// PORTB = 8-bit switch inputs
                     
  PORTA.7 = 0         '// Transmitter IR LED = off  RA.7 ----|>|----/\/\/\---gnd
                      '// Note: RA.7 can drive an NPN transistor for longer range
  TRISA = %01111111   '// PORTA.7 = output LED drive. Rest inputs for address
  GoTo Encode         '// Mode = Encode, jump over sub to Encode routine

This is just to give you an idea there may be better ways of doing it

BTW boards look nice

[joesaliba]

Hi,

Is it a 915MHz FSK data transfer transceiver good to use with this code?

Thank you
Regards

Joseph

[Sean_Goddard]

Originally Posted by Tim

OK I have sent out a few mails to those I can find an address for (inc Steve)

I need a e-mail address for

ahmet
Barak
Frizie
Paul V
and Sean_Goddard

Please could you PM so I can e-mail you the files

Tim, can you PM me this file or use the email address I use for this site. I've just updated it. Sorry I forgot I'd changed it for SPAM reasons

Thx

[Tim]

At the moment the code in in trial and going out to licensed users.

It will be made public later

[Sean_Goddard]

Not sure WHY I'm not down as a licensed user, but I should be (I think) as I bought the full Proton package quite a while ago now, in fact I bought two!

[wastrix]

Use the instructions here to becoime a licensed user: http://wiki.picbasic.org/index.php?n...orumUserStatus

[Sean_Goddard]

GREAT, now all I have to do is sift through 5 years of invoices to find my invoice number!

I've emailed CH to see if they can help, failing that, there should be some other way involving the dongle (ooh painful)!

[Tim]

I have PM'd you but I still recommend you sign up. If you purchased it from Crownhill they will have a record of it.