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PropScope Help..capture waveforms of Propeller to dual MotorMount w Position co — Parallax Forums

PropScope Help..capture waveforms of Propeller to dual MotorMount w Position co

johnsoperV52johnsoperV52 Posts: 10
edited 2010-03-08 21:49 in Accessories
 currently I cannot afford PropScope but wish if someone has this and can help. See Details below.

·· PropScope Help..capture waveforms of Propeller to dual MotorMount w Position controllers and dual HB-25s using MPC_Roll_Demo.spin

 

Has any one tested MPC_Roll_Demo.spin in this specific configuration? i.e.

Demo of the Wheel and Motor Mount kit (27971) and HB-25's (29144). Uses the Simple-Serial.spin object that is included with the Propeller Tool.

After confirming I have conformed to all the directionsin wiring.

The motors will not respond with any motion at all.

For troubleshooting:

1) confirmed proper connections i.e. Per MPC_Roll_Demo.spin Schematic.

2) confirmed all components and connectors and cables good and hooked per directions.

3) I successfully ran the same motor configuration and position controller with BS2 using the BS2 Demo, i.e. per

http://www.parallax.com/Portals/0/Downloads/docs/prod/motors/PositionControllerTestInterface(v1_2_1).zip

4) I have Digital Storage Scope waveform captures of communications from Prop "I/O Pin" and "Data Pin" on Position Controller and I have analyzed them bit for bit and the bit wise logic is consistent with page 17 (Communications Protocol) of http://www.parallax.com/Portals/0/Downloads/docs/prod/motors/27971-MotorMount-v1.3.pdf.

I have for comparison captured BS2 waveforms that actually result in proper expected motor motion.

There logic bit for bit compares but that is not the problem, I suspect w2rong in timing , i.e. the start bit has a significant voltage transition uSecondsbefore each Start Bit.

The problem with the Propeller version of this experiment is 3.3 volt to 5 Volt and the interactions between the electronics in the Prop and Position Sensor.

The waveforms and a viewer are available for the request for any intrepid soul that can help.

Comments

  • johnsoperV52johnsoperV52 Posts: 10
    edited 2010-03-08 21:31
    I understand Josh in Tech Support has identified the problem.
    The call to Simple_Serial.spin needed a delay following that call, 500mSec is needed for Simple_Spin to initialize for proper use.

    Thank You Tech Support, Josh.
  • hover1hover1 Posts: 1,929
    edited 2010-03-08 21:49
    Good info John.

    Thanks! And thanks to Josh, he's great!

    Jim
    johnsoperV52 said...
    I understand Josh in Tech Support has identified the problem.
    The call to Simple_Serial.spin needed a delay following that call, 500mSec is needed for Simple_Spin to initialize for proper use.

    Thank You Tech Support, Josh.
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