HB-25 SPIN Question

NWCCTV · 2013-07-09 15:37

I am anxiously awaiting the arrival of my Wild Thumper robot which will be here tomorrow. While I am waiting I am working on getting my SPIN code for the IR Remote to work with it. It comes with 2 Ea. HB-25's. Several months ago I wrote the code for 2 HB-25's to work using Parallax IR receiver and a standard remote control for another project using PBasic. In PBasic, you must issue a pause 1 command immediately after the first PULSEOUT command to start the second HB-25. Do I do the same thing in SPIN? PBasic code example below.

IF (IN3 = 1)  THEN        ' Checks if Pushbutton on IN3 is pressed,
                          ' If Yes then send pulseout command to Pin
    PULSOUT HB25, 500     ' 15  to rotate motor 1 forward.
    PAUSE 1               ' 1 mS Delay For Motor 2 Pulse
    PULSOUT HB25, 1000    ' send pulsout command to pin 15
                          ' to rotate motor 2 reverse.
    PAUSE 10                ' wait 10 ms

JonnyMac · 2013-07-09 15:56

You can use one of the counters to create a high precision pulse output. It's not quite the same as the BS2 PULSOUT (which inverts the pin state), but for your purposes this will work (I use it for servo pulses all the time). As PAUSE is not part of the Spin language I've included my method for that, too.

pub pulse_out(pin, us)

'' Creates active-high pulse output on pin (timing in microseconds)
'' -- leaves pin a output low

  us *= (clkfreq / 1_000_000)                                   ' convert to ticks

  phsa := 0  
  frqa := 1                                                     
  ctra := (%00100 << 26) | pin                                  ' NCE/SE mode
  dira[pin] := 1                                                ' make pin an output

  phsa := -us                                                   ' start the pulse
  waitpne(1 << pin, 1 << pin, 0)                                ' let it finish


pub pause(ms) | t

'' Delay program in milliseconds

  if (ms < 1)                                                   ' delay must be > 0
    return
  else
    t := cnt - 1776                                             ' sync with system counter
    repeat ms                                                   ' run delay
      waitcnt(t += (clkfreq / 1000))

Converting your PBASIC fragment:

if (ina[3] == 1)
    pulse_out(HB25, 1000)
    pause(1)
    pulse_out(HB25, 2000)
    pause(10)

Remember that BS2 PULSOUT units are 2us each; the pulse_out() method uses 1us units, hence the change in the values.

NWCCTV · 2013-07-09 17:04

Thanks Jon. I was aware of this, I just posted my code as an example.

HB-25 SPIN Question

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