RF Transmitter/Receiver (#27980)

Comments

• Franklin Posts: 4,747

  2010-07-01 01:59 edited 2010-07-01 01:59

  The transmitter is designed to transmit so that should work but what are you using to receive? What is it you need exactly and have you looked at the parallax site for sample code?
  

  ' TxCode_v_1.0.bs2
  '{$STAMP BS2}
  '{$PBASIC 2.5}
  '
  'Parallax 433.92 MHz RF Receiver (#27981) Sample Tx Code (BS2)
  'Connect Pin 8 of the BS2 to the DATA line on the RF module
  'Connect +5v to the 5v line, connect Ground to the GND line
  'This code will transmit two word sized counters, byte at a time.
  '
  'Note the PULSOUT instruction: this helps the receiver sync with
  'the transmitter, especially after lapses in communication
  'This code transmits at 9600 baud, inverted.
  x VAR Word
  y VAR Word
  DO
  PULSOUT 8, 1200 'Sync pulse for the receiver
  SEROUT 8, 16468, [noparse][[/noparse] "!", x.HIGHBYTE, x.LOWBYTE, y.HIGHBYTE, y.LOWBYTE ]
  x = x + 1
  y = y + 1
  PAUSE 10
  LOOP
  

  
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  - Stephen
  
  Post Edited (Franklin) : 7/1/2010 2:04:05 AM GMT
• James2010NG Posts: 10

  2010-07-01 12:57 edited 2010-07-01 12:57

  We already used that code. We want to use the DEBUG terminal to try and send a signal to the RF transmitter to send a certain code to the receiver? Is this possible? You can change the transmitter code to send certain letters or numbers as the signals. So can I (for instance), enter a 0 into the transmitter DEBUG terminal and get a certain code (using IF...THEN)? Possibly with the DEBUGIN command?
• Mike Green Posts: 23,101

  2010-07-01 14:56 edited 2010-07-01 14:56

  The DEBUG and DEBUGIN statements are really special cases of the SEROUT and SERIN statements with the pin number parameter equal to 16 and some simplification of the other parameters. The Parallax example you showed simply illustrates the transmission of two 16-bit binary numbers. You can send anything you want.
  
  Keep in mind that there may be a lot of radio noise present and there may be errors in the information received. It's good practice to use some kind of error detection. There are some examples with links on the product webpage on the use of CRC (cyclic redundancy checks) with the transmitter/receiver. The use of "!" or similar lead-in character also helps. In simple cases, you could just send the same data two or three times with different lead-in characters to get the redundancy.