HB25 and Position Controller RX transmission

Pedrito · 2010-05-11 17:53

Hello,

I am using the Motor Mount and Wheel Kit with Position Controllers and 2 HB-25 motor controllers. The connection seems to be right because I can send information to the wheels, and they travel any position, but when I want the current position from the encoders, I don't get any data at all.

The odd part is that I can send information to the encoders, but I dont get anything back. The code I am testing is straight forward from the code given from parallax.

The program gets stuck in the "DisplayPosition" subroutine in "SERIN".

Thanks for your help!
Pedro

' {$STAMP BS2pe}
' {$PBASIC 2.5}

'--- Command Value Constants ---
QPOS         CON      $08            'Query Position
QSPD         CON      $10            'Query Speed
CHFA         CON      $18            'Check for Arrival
TRVL         CON      $20            'Travel Number of Positions
CLRP         CON      $28            'Clear Position
SREV         CON      $30            'Set Orientation as Reversed
STXD         CON      $38            'Set TX Delay
SMAX         CON      $40            'Set Speed Maximum
SSRR         CON      $48            'Set Speed Ramp Rate

'--- User Constants & Variables ---
AllWheels    CON      0
RightWheel   CON      1              'ID of the right side Position Controller
LeftWheel    CON      2              'ID of the left side Position Controller
CommPin      PIN      2             'communication bus pin
BaudValue    CON      32             'for 19.2kbps
Wheel        VAR      Byte           'Specifies which wheel to command for subroutines
Distance     VAR      Word           'Used to set the travel distance
RxData       VAR      Word           'Used to receive data

'--- Initialization ---
PAUSE 1000
SEROUT CommPin, BaudValue, [noparse][[/noparse]SREV + RightWheel]  'Reverses the sensor on the right
SEROUT CommPin, BaudValue, [noparse][[/noparse]CLRP]               'Clears any prior position info

'Go forward 350 positions
Wheel = AllWheels
Distance = 200
GOSUB GoDistance

'Continually check the position of each wheel
CheckLoop:
  Wheel = LeftWheel   'LeftWheel
  DEBUG "L= "
  GOSUB DisplayPosition
  Wheel = RightWheel
  DEBUG "  R= "
  GOSUB DisplayPosition
  DEBUG CR
  GOTO  CheckLoop
  END

'--- Subroutines ---
GoDistance:
  SEROUT CommPin, BaudValue, [noparse][[/noparse]TRVL + Wheel]
  SEROUT CommPin, BaudValue, [noparse][[/noparse]Distance.HIGHBYTE, Distance.LOWBYTE]
RETURN

DisplayPosition:
  SEROUT CommPin, BaudValue, [noparse][[/noparse]QPOS + Wheel]
  SERIN  CommPin, BaudValue, [noparse][[/noparse]RxData.HIGHBYTE, RxData.LOWBYTE]
RETURN

JD · 2010-05-11 19:22

Pedrito,
Do you happen to have an oscilloscope that you can watch the TX to verify that the signal is being sent from the position controller to the BASIC Stamp 2pe? Have you tried another IO pin to see if the issue is IO pin related?

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Respectfully,

Joshua Donelson
www.parallax.com

HB25 and Position Controller RX transmission

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