Variable overwriting another variable

Mcadieux · 2009-02-23 23:59

I'm new to spin so hopefully this isn't something really stupid I am doing wrong. The problem I am having is when I write to one of my variables it is actually overwriting a different variable.

This is my variable definition block:

VAR
  
  long centerPos, servoPos, Dot
  long temporary, newPos, degMax, degMin
  
  byte Cog

This is where the temp variable is used:

PUB setDeg(servo, deg) 
  temporary := (controller.getHighLimit(servo) - controller.getLowLimit(servo)) / DOT[noparse][[/noparse]servo]
  newPos := (deg * temporary) + centerPos[noparse][[/noparse]servo]
  servoPos[noparse][[/noparse]servo] := newPos
  controller.Set(servo, servoPos[noparse][[/noparse]servo])

The problem is instead of the number being assigned to temp it is sent to DOT. This has me stumped.

Ken Peterson · 2009-02-24 00:53

Why are you indexing a variable that is not defined as an array?

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·"I have always wished that my computer would be as easy to use as my telephone.· My wish has come true.· I no longer know how to use my telephone."

- Bjarne Stroustrup

rokicki · 2009-02-24 00:53

Your "servoPos" is an array of one element, indexed starting at 0.

My guess is your server argument is set to *1*, not *0*.

Always, for cases like this, please attach full code.

Mcadieux · 2009-02-24 01:11

The brackets don't seem to show up my variable block is actually:

VAR

long centerPos[noparse][[/noparse]10], servoPos[noparse][[/noparse]10], Dot[noparse][[/noparse]10]
long temporary, newPos, degMax, degMin

byte Cog 'Holds the cog that the controller was launched into

GeorgeCollins · 2009-02-24 04:04

I think I would need to see more code to know for sure, but a guess would be that you are finding that the value you expect to be in temporary is also in Dot[noparse][[/noparse]10], which == temporary

That may not be what is going on, but I think we need to see more code to know for sure.

Mcadieux · 2009-02-24 05:33

Ok here is the complete code, it's kind of messy. Its probably not the best most optimized way of doing things but im trying to get used to spin. The variable called cheapfix was my way of fixing the code for now. Instead of overwriting my last DOT variable it overwrites cheapfix. The reason temp is global is so that I could use viewpoint to view it since the code was acting funny. Thanks for the help so far.

{{ Output.spin }}
VAR
  
  long centerPos[noparse][[/noparse]10], servoPos[noparse][[/noparse]10], Dot[noparse][[/noparse]10]
  long cheapfix, temp, newPos[noparse][[/noparse]10], degMax, degMin
  long reverseStatus[noparse][[/noparse]10]
  
  byte Cog 'Holds the cog that the controller was launched into

OBJ
  controller : "MyServo32v3"
     


PUB setup(pinStart, pinEnd) | pinrange
{{Sets all pins between start and end to output and sets initial position to servo center.
It also sets default end point limits to avoid servo damage.
This must be called before servo START}}

  repeat pinrange from pinStart to pinEnd 'Preset ALL servo's to center position
    controller.Set(pinrange,1000)
    controller.setHighLimit(pinrange, 2250)
    controller.setLowLimit(pinrange, 225)
 

PUB start
{{Starts the Controller must be called AFTER setup and before all other commands}}
  controller.Start

  
PUB setCenter(servo, pos)
  {{Set the center position of each servo. This becomes 0 Deg's}}
  centerPos[noparse][[/noparse]servo] := pos
  servoPos[noparse][[/noparse]servo] := pos
  controller.Set(servo, centerPos[noparse][[/noparse]servo])

PUB center(servo)
  servoPos[noparse][[/noparse]servo] := centerPos[noparse][[/noparse]servo]
  controller.Set(servo, centerPos[noparse][[/noparse]servo])
  
PUB setDeg(servo, deg) 
 {{Sets the servo using degrees must be between degMax and degMin}}
  temp := (controller.getHighLimit(servo) - controller.getLowLimit(servo))/ DOT[noparse][[/noparse]servo] 'Calculate how many degrees per ms
  newPos[noparse][[/noparse]servo] := (deg * temp) + centerPos[noparse][[/noparse]servo]
  servoPos[noparse][[/noparse]servo] := newPos[noparse][[/noparse]servo]
  controller.Set(servo, servoPos[noparse][[/noparse]servo]) '
 

PUB setDot(servo, deg)
{{This tells the controller how many degrees of travel the servo is able to move. This must be adjusted
if the end point limits are changed}}
  Dot[noparse][[/noparse]servo] := deg  

PUB getPos(servo) : position
{{return the current position of the servo}}
  position := servoPos[noparse][[/noparse]servo]



PUB setPos(servo, pos)
{{Set the position of the servo to a specific point. The controller will still stay between the endpoints}}
  servoPos[noparse][[/noparse]servo] := pos
  controller.Set(servo, servoPos[noparse][[/noparse]servo]) '



PUB increasePos(servo, val) | tem
{{Increase the servo position by a specific ms value}}
  tem := servoPos[noparse][[/noparse]servo] + val
  servoPos[noparse][[/noparse]servo] := tem
  controller.Set(servo, servoPos[noparse][[/noparse]servo]) '


PUB decreasePos(servo, val) | tem
{{Decrease the servo position by a specific ms value}}
  tem := servoPos[noparse][[/noparse]servo] - val
  servoPos[noparse][[/noparse]servo] := tem
  controller.Set(servo, servoPos[noparse][[/noparse]servo])


PUB setHighLimit(servo, value)
{{Sets the High END POINT of Servo}}
  controller.setHighLimit(servo, value)


PUB setLowLimit(servo, value)
{{Sets the low end point of servo}}
  controller.setLowLimit(servo, value)   

PUB reverse(servo, status)
  reverseStatus[noparse][[/noparse]servo] := status

Post Edited (Mcadieux) : 2/24/2009 5:48:11 AM GMT

rokicki · 2009-02-24 05:41

Please, *full* code. It really does help.

mpark · 2009-02-24 15:22

Mcadieux,

If you want help, you have to post your entire program, not just output.spin. The problem might lie in the code that calls the methods in output.spin.

Mcadieux · 2009-02-24 17:40

Ok, here is all the code, sorry for the delay. My 6 month old was sick last night and wasn't really letting me get anything done. Now it seems to be acting normal, but I haven't changed anything. Here is the code anyway. I know it isn't optimized, but it is more about trying to get the language down. I believe the problem may have been how I was interpreting viewport. I was thinking of an array[noparse][[/noparse]10] as 1 - 10 instead of 0-9.

{{ Output.spin }}
VAR
  
  long centerPos[noparse][[/noparse]10], servoPos[noparse][[/noparse]10], Dot[noparse][[/noparse]10]
  long cheapfix, temp, newPos[noparse][[/noparse]10], degMax, degMin
  long reverseStatus[noparse][[/noparse]10]
  
  byte Cog 'Holds the cog that the controller was launched into

OBJ
  controller : "MyServo32v3"
  vp:"Conduit"    


PUB setup(pinStart, pinEnd) | pinrange
{{Sets all pins between start and end to output and sets initial position to servo center.
It also sets default end point limits to avoid servo damage.
This must be called before servo START}}
  vp.share(@Dot, @newPos)

  repeat pinrange from pinStart to pinEnd 'Preset ALL servo's to center position
    controller.Set(pinrange,1000)
    controller.setHighLimit(pinrange, 2250)
    controller.setLowLimit(pinrange, 225)
 

PUB start
{{Starts the Controller must be called AFTER setup and before all other commands}}
  controller.Start

  
PUB setCenter(servo, pos)
  {{Set the center position of each servo. This becomes 0 Deg's}}
  centerPos[noparse][[/noparse]servo] := pos
  servoPos[noparse][[/noparse]servo] := pos
  controller.Set(servo, centerPos[noparse][[/noparse]servo])

PUB center(servo)
  servoPos[noparse][[/noparse]servo] := centerPos[noparse][[/noparse]servo]
  controller.Set(servo, centerPos[noparse][[/noparse]servo])
  
PUB setDeg(servo, deg) 
 {{Sets the servo using degrees must be between degMax and degMin}}
  temp := (controller.getHighLimit(servo) - controller.getLowLimit(servo))/ DOT[noparse][[/noparse]servo] 'Calculate how many degrees per ms

  if reverseStatus[noparse][[/noparse]servo] == 0
    newPos[noparse][[/noparse]servo] := centerPos[noparse][[/noparse]servo] +(deg * temp)
  if reverseStatus[noparse][[/noparse]servo] == 1
    newPos[noparse][[/noparse]servo] := centerPos[noparse][[/noparse]servo] - (deg * temp)

  servoPos[noparse][[/noparse]servo] := newPos[noparse][[/noparse]servo]
  controller.Set(servo, servoPos[noparse][[/noparse]servo]) '
 

PUB setDot(servo, deg)
{{This tells the controller how many degrees of travel the servo is able to move. This must be adjusted
if the end point limits are changed}}
  Dot[noparse][[/noparse]servo] := deg  

PUB getPos(servo) : position
{{return the current position of the servo}}
  position := servoPos[noparse][[/noparse]servo]



PUB setPos(servo, pos)
{{Set the position of the servo to a specific point. The controller will still stay between the endpoints}}
  servoPos[noparse][[/noparse]servo] := pos
  controller.Set(servo, servoPos[noparse][[/noparse]servo]) '



PUB increasePos(servo, val) | tem
{{Increase the servo position by a specific ms value}}
  tem := servoPos[noparse][[/noparse]servo] + val
  servoPos[noparse][[/noparse]servo] := tem
  controller.Set(servo, servoPos[noparse][[/noparse]servo]) '


PUB decreasePos(servo, val) | tem
{{Decrease the servo position by a specific ms value}}
  tem := servoPos[noparse][[/noparse]servo] - val
  servoPos[noparse][[/noparse]servo] := tem
  controller.Set(servo, servoPos[noparse][[/noparse]servo])


PUB setHighLimit(servo, value)
{{Sets the High END POINT of Servo}}
  controller.setHighLimit(servo, value)


PUB setLowLimit(servo, value)
{{Sets the low end point of servo}}
  controller.setLowLimit(servo, value)   

PUB setReverse(servo, status)
  reverseStatus[noparse][[/noparse]servo] := status

{{main}}
VAR
  long  stack[noparse][[/noparse]10]
  long temp
CON
                  
  _xinfreq = 5_000_000                      
  _clkmode = xtal1 + pll16x


OBJ

  controller : "ServoController0.6"

  

PUB Main
  controller.setup(1,1)
  controller.start
  controller.setCenter(1,1000)
  controller.setDOT(1, 160)

  
  repeat
    controller.setCenter(1,1000)
    waitcnt(clkfreq * 3 + cnt)
    controller.setDeg(1,45)
    waitcnt(clkfreq * 3 + cnt)
    controller.setCenter(1,1000)
    waitcnt(clkfreq * 3 + cnt)
    controller.setDeg(1,-45)
    waitcnt(clkfreq * 3 + cnt)

The MyServo32v3 object is just your standard Servo32v3 object. I deleted cheapfix temporary and made temp back to a local variable and it seems to work fine now. I may have just been doing something stupid last night. Thanks for trying to help, sorry I was brain dead about posting code last night.

Mcadieux · 2009-02-24 20:26

Ok, I figured out what I did. It wasn't temp overwriting DOT it was DOT overwriting temp. I was writing past the end of the array. Considering I know C++ this was a dumb mistake. Thanks for trying to help me.

Ken Peterson · 2009-02-24 20:37

I was going to suggest that at first, as you always have to be conscious of that with indexed variables.· But since you said temporary was overwritten instead of Dot, that wouldn't have explained it.

Glad you figured it out.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
·"I have always wished that my computer would be as easy to use as my telephone.· My wish has come true.· I no longer know how to use my telephone."

- Bjarne Stroustrup

Variable overwriting another variable

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