30m Beacon - a 20 min Effort

So how easy was it to Program a CW and QRSS FSK Beacon with the Propeller? See previous post.

Well here is the code of the Main program, followed by the supplied Synthesizer Library. Note: in the Propeller "Spin"Programming Language, line indents (i.e., TABs or spaces) are important. They define the programming constructs for loops and other structures.

The Main Program

CON

  _CLKMODE = XTAL1 + PLL16X
  _XINFREQ = 5_000_000

  RFPin  = 27

  ReceiverDial = 10_138_700
  TuneOffset   =      1_300

  Frequency = ReceiverDial + TuneOffset          'DC to 128MHz


VAR

OBJ
  Freq : "Synth"
  
PUB Main | i
  repeat
    ' Send my Call via CW
    sendCWstr(string("de WA0UWH"))
    delay(2000)

    ' For fun, Generate 5 QRSS tones
    repeat i from 0 to 4
       sendTone(50+2*i)
       delay(3000)
       noTone
       delay(3000)

    delay(12000)

PUB delay(ms)
  waitcnt(cnt + clkfreq/1000 * ms)

PUB sendCWstr(stringptr)
  repeat strsize(stringptr)
      sendCWchr(byte[stringptr++])

PUB sendCWchr(char)    'A lookup Table of CW character

  case char
   " ":
    noTone
    delay(700)
    return

   "A", "a":
    dot
    dash
   "B", "b":
    dash
    dot
    dot
    dot
   "C", "c":
    dash
    dot
    dash
    dot

    . . . .

   "9":
    dash
    dash
    dash
    dash
    dot
   "0":
    dash
    dash
    dash
    dash
    dash

   "@":
    dot
    dash
    dash
    dot
    dash
    dot

  noTone
  delay(300)   ' Delay between each character

PUB sendTone(tone)
  Freq.Synth("A",RFPin, Frequency + tone)

PUB noTone
 Freq.Synth("A",RFPin, 0)


PRI dot
    sendTone(50)
    delay(100)
    noTone
    delay(100)


PRI dash
    sendTone(50)
    delay(300)
    noTone
    delay(100)

Here is the supplied Libaray

PUB Synth(CTR_AB, Pin, Freq) | s, d, ctr, frq

  Freq := Freq #> 0 <# 128_000_000     'limit frequency range
  
  if Freq < 500_000                    'if 0 to 499_999 Hz,
    ctr := constant(100 << 26)      '..set NCO mode
    s := 1                             '..shift = 1
  else                                 'if 500_000 to 128_000_000 Hz,
    ctr := constant(010 << 26)      '..set PLL mode
    d := >|((Freq - 1) / 1_000_000)    'determine PLLDIV
    s := 4 - d                         'determine shift
    ctr |= d << 23                     'set PLLDIV
    
  frq := fraction(Freq, CLKFREQ, s)    'Compute FRQA/FRQB value
  ctr |= Pin                           'set PINA to complete CTRA/CTRB value

  if CTR_AB == "A"
     CTRA := ctr                        'set CTRA
     FRQA := frq                        'set FRQA                   
     DIRA[Pin]~~                        'make pin output
     
  if CTR_AB == "B"
     CTRB := ctr                        'set CTRB
     FRQB := frq                        'set FRQB                   
     DIRA[Pin]~~                        'make pin output

PRI fraction(a, b, shift) : f

  if shift > 0                         'if shift, pre-shift a or b left
    a <<= shift                        'to maintain significant bits while 
  if shift < 0                         'insuring proper result
    b <<= -shift
 
  repeat 32                            'perform long division of a/b
    f <<= 1
    if a => b
      a -= b
      f++           
    a <<= 1

This 30m Beacon is running on; a Parallax Propeller, a 9Volt Battery, and two short 3 inch wires for the antenna.

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