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Input For PIC uC

Discussion in 'Microcontrollers' started by mesamune80, Apr 30, 2008.

  1. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi,
    NO,
    Look at the TRISC..... 0 = 0utput... 1 = 1nput

    The format of the binary number 00001111, is b7,b6,b5,b4,b4,b3,b2,b1,b0

    As PORTC.6 is 0 in the TRISC it an OUTPUT. Set it to 1
    example:
    TRISC = %01001111

    I have run your code in the simulator with TRISC= %01001111 and it works OK.
     
  2. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi mesamune,
    I am wondering if your misunderstanding of Input and Output is due to thinking that,
    OUTPUT refers to the output of the Comparator, not the PIC pin.?

    The TRIS set the pin configuration of the PIC pins not the external devices.

    Do you follow.?
     
  3. mesamune80

    mesamune80 New Member

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    Opss. i think i got it another way round,that's why i cant get the desired result,thanks for your clarification. ^_^
     
  4. dave

    Dave New Member

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  5. mesamune80

    mesamune80 New Member

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    Hi eric could you give some advice on how to drive this motor?

    because i had tried the normal way to run th motor,but it seem to not moving at all.i wonder why.

    http://catalog.orientalmotor.com/it...20?&plpver=11&origin=keyword&filter=&by=prod#

    i wired my pulse input to CW/P.+ (pin for the motor driver)with high 250us and low 500us

    and direction i pump high to the pin CCW/D.+ for my motor direction.

    Thanks. =)
     

    Attached Files:

  6. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi mesamune,
    I'll look the documentation, you do realise its a 5 phase stepper motor.?

    Are you meeting ALL the criteria for driving this type of motor.?

    I have posted an extract from their data.
     
    Last edited: Jul 7, 2008
  7. mesamune80

    mesamune80 New Member

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    Ya i folow exactly what it said to drive the motor but i dunno what i missed out as my motor not moving :(
     
  8. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi,
    Can you post ALL of the PIC program so that we can see the method that you are using.?

    If its in 'C language' someone else will help out, I write in assembler.
     
  9. mesamune80

    mesamune80 New Member

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    this is my test program ,cos i want to make sure this motor can run 1st

    Symbol pulse1 = PORTC.0 'pulse for m1
    Symbol dir1 = PORTC.1 'direction for m1
    Symbol pulse2 = PORTC.2
    Symbol dir2 = PORTC.3 'direction for m2 vexta

    TRISC = %11110000

    loop:

    dir2 = 1
    High PORTC.2 'pulse M2
    WaitUs 250
    Low PORTC.2 'pulse M2
    WaitUs 500

    Goto loop

    End
     
  10. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi,
    A quick look at the 'program' would suggest to me that it does not meet the requirements of the motor.!:)

    Do you have a copy of the manufacturers software/program.?
     
  11. mesamune80

    mesamune80 New Member

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    i am using PIC uC PIC16F877 to control this motor ,software i am using PIC Simulator IDE (basic based)but according to the manual i need to power up the pulse pins and also the directional pin is it? i mean pin 1 and pin 3 i need to connect to 5VDC and pin 2 and 4 to pulse input pin (PORTC.2) and (PORTC.3) one output pulse signal and another one direction signal.
     
  12. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi,
    You must meet the requirements of the motor as shown in the extract attached.

    Do you have the controller and the motor.?
    The controller expects to be driven from a MCU.
     
    Last edited: Jul 7, 2008
  13. mesamune80

    mesamune80 New Member

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    ya i am driving the controller with PIC uC, it seem my motor are now working,as i though the controller is internally power up.after study the extract which you posted it need to connect to VDC because b 4 this i straight away connect the uC input to the corresponding pin without any power go in to the corresponding pin :)
     
    Last edited: May 16, 2008
  14. mesamune80

    mesamune80 New Member

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    Hi eric now i have 1 issue ,the problem is my motor rotate in a slow speed how can i speed it up it is SLOW.....=_="
     
  15. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi,
    Are you pulsing the motor as specified in the datasheet, ie 10uSec with a 50%duty cycle.

    Have you checked the pulse waveform using an oscilloscope, also what supply voltage do you have to the motor.?
     
    Last edited: May 25, 2008
  16. mesamune80

    mesamune80 New Member

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    i am using pulse like

    loop:

    dir2 = 1
    High PORTC.2
    WaitUs 500
    Low PORTC.2
    WaitUs 500
    Goto loop

    the motor is geared so is 0.036 degree/pulse (basic step angle)

    Gear ratio is 20:1

    so all this will resulted in my very slow output.

    my motor driver is powered with 24VDC.
     
  17. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    Hi,
    Looking at these figures, it will be slow, reduce the pulses to say 50uSec as a starting point.
    If that works OK, reduce to 25usec and retest.

    Lets know what you find.:)
     
  18. mesamune80

    mesamune80 New Member

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    okay i'll try it out this one.thanks.
     
  19. mesamune80

    mesamune80 New Member

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    Eric sorry for late reply,i just tried out the timing just now ,i used 50us for 50% duty cycle pulse,the speed had improved but it still quite slow i do you think this is how far it can go?
     
  20. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi,
    Look at my May15 posted drawing... the limit is 5uSec, which should make it ten times faster than 50uSec, providing your motor is able to respond to 5uSec pulses...OK.

    As I suggested, keep reducing the pulse time until you find the motors limit.
     
  21. mesamune80

    mesamune80 New Member

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    OK,i;ll try doing that hiope can get the motor fastest speed that i desired. thanks!!! ^_^
     

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