My SPIN logic is misbehaving

garyg · 2014-09-11 18:13

Hi

I'M attempting to get my LCD display to show two different motor speeds.
When I press the P7 touch button, the MOTOR 2 speed should be reduced by 8.
This fairly works.

MOTOR1 should be displaying a value of 1111 on the LCD display, but it displays -1.
The PUB speed LCD should only update if a the button is pressed but the loop continues all the way always.

Any help with resolving this situation would help a lot
Thanks
.

OBJ

  LCD      : "FullDuplexSerial.spin"
  Buttons  : "Touch Buttons"                        
CON
  _clkmode = xtal1 + pll16x
  _xinfreq = 5_000_000

  TxPin = 8   'TXPIN IS PIN #8 ON THE QUICKSTART BOARD.
VAR
  LONG STACK[20]
  long sp3 
  long sp1
  long sp2
  long flag1 
  
PUB Main
  sp1 := 1111
  sp2 := 9999
  sp3 := 1111
  flag1 := 0
 Buttons.start(_xinfreq / 6)                         ' Launch the touch buttons driver sampling 100 times a second
  dira[23..16]~~                                        ' Set the LEDs as outputs 

 LCD.start(TxPin, TxPin, %1000, 9_600)
  WaitCnt(ClkFreq / 100 + Cnt)          ' Pause to initialize
  LCD.tx(12)                            ' Clear
  LCD.tx(17)                            ' Turn on backlight
  LCD.str(String("Motor1"))    ' First line
  LCD.tx(13)                            ' Line feed
  LCD.str(String("Motor2"))     ' Second line
  LCD.tx(212)                           ' Set quarter note
  LCD.tx(220)                           ' A tone             
  WaitCnt(ClkFreq * 3 + Cnt)            ' Wait 3 seconds
  LCD.tx(18)                            ' Turn off backlight
  
 

speed                           'speed calls the Speed object to run                                   
PUB Speed
  repeat
      outa[23..16] := Buttons.State
      flag1 :=outa[23]
      if flag1 ==1
        sp2:= sp2-8
      flag1:=0
      if sp3<>= sp2           'Only update the LCD if the speed number has changed.
         LCD.TX(136)                    'Move cursor to line 0, position 8
         LCD.Dec(sp3)              'Print Motor1 speed to LCD
         LCD.TX(156)                   'Move cursor to line1, position 8
         LCD.Dec(sp2)              'Print Motor2 speed to LCD
          LCD.tx(17)                            ' Turn on backlight
         WaitCnt(ClkFreq * 1 + Cnt)            ' Wait 1 second
         ' sp3:= sp2+0                         ' sets sp3 equal to current speed number sp2
         LCD.tx(212)                           ' Set quarter note
         LCD.tx(220)                           ' A tone        This tells me if this part of the loop was executed.
         WaitCnt(ClkFreq * 3 + Cnt)            ' Wait 3 seconds

kuroneko · 2014-09-11 18:23

garyg wrote: »

MOTOR1 should be displaying a value of 1111 on the LCD display, but it displays -1.

This is because of if sp3 <>= sp2, it does the comparison but also assigns the result (TRUE(-1)/FALSE(0)) to sp3. Better to just stick with <> and update sp3 manually later.

For code display use [noparse]

[/noparse].

garyg · 2014-09-11 18:51

Thanks
Your suggestions worked out very good.
The loop only runs when the pushbutton changes, otherwise it's is skipped.

I was able to add the ' sp3:= sp2+0 ' sets sp3 equal to current speed number sp2

Is updating the sp3 value in the above manner the best way to do that?
It appears to work, but it would seem to me like sp3:=sp2 should also work but it did not seem to work.

kuroneko · 2014-09-11 18:59

Using sp3 := sp2 is fine inside the if (after the old value is displayed if that's required).

garyg · 2014-09-11 19:36

I see what you are saying.
When I 1st power up the quickstart and LCD display, my default sp2 and sp3 settings are displayed.
After the 1st button press, the Motor1 and Motor2 displayed numbers are always 8 different.

For this particular application, it really does not matter.
I was using the default settings of sp2 and sp3 as a start.
The end result was exactly what I was looking for.

I'll be using this strategy to control the speed of HB25 motor controllers with a Parallax Keyfob remote.

Thanks
You made my day.

My SPIN logic is misbehaving

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