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Software => Software => Topic started by: orchid on February 21, 2008, 10:28:11 PM

Title: tms320f2812
Post by: orchid on February 21, 2008, 10:28:11 PM
hi all,

i would like to know if there are somebody use mck2812 (motion control kit)?
can you all help me on how to control the motor using ccs?
need your help

thanks,
Title: Re: tms320f2812
Post by: airman00 on February 21, 2008, 10:29:49 PM
be specific about your problem and maybe even those people who dont have that kit can help you out
Title: Re: tms320f2812
Post by: orchid on February 22, 2008, 01:38:31 AM
i dont know how to make the motor to rotate 360 degree. i am using 3 phase brushless dc motor.
Title: Re: tms320f2812
Post by: Admin on February 23, 2008, 03:05:37 PM
Did you read the MCK2812 manual?

Tell us what you already have done, and where you are stuck.
Title: Re: tms320f2812
Post by: orchid on February 24, 2008, 07:46:22 PM
i have read the manual, but i cant really adapt the instruction to my programme because it using assembly language.i am using c code.in the manual, it explain on how to use evaluation programme but when i try to adapt the software into my source code, it didnt work out well. thats make me blur. ???
Title: Re: tms320f2812
Post by: Admin on February 27, 2008, 08:08:10 PM
Can you tell us about your control hardware, and why you are programming using C?

(tell us more about your setup)
Title: Re: tms320f2812
Post by: orchid on February 27, 2008, 10:36:51 PM
do anyone have a source code in c to make the motor rotate 360 degree?
i have try make source code on my own but the motor not spinning. it just move a little, stop, and then the motor start buzzing. why is it my motor not spinning but make sound.what is the cause?do anyone know how to solve the problem?here some of the source code that i have done.
Code: [Select]
{ EvaRegs.ACTRA.all = 0x0000; // all PWM pins forced low initially
   
   if(AdcRegs.ADCRESULT0 > 0x0900 && AdcRegs.ADCRESULT0 < 0x10FF)
   {
   GpioDataRegs.GPBDAT.all = 0xFFFB;
   EvaRegs.T1PR = 0x03A9;//10kHz

EvaRegs.ACTRA.all = 0x00C2;
// EvaRegs.ACTRA.all = 0x0C02;
// EvaRegs.ACTRA.all = 0x0C20;
// EvaRegs.ACTRA.all = 0x002C;
// EvaRegs.ACTRA.all = 0x020C;
// EvaRegs.ACTRA.all = 0x02C0;
}
Title: Re: tms320f2812
Post by: Admin on March 09, 2008, 08:59:41 AM
Quote
it just move a little, stop, and then the motor start buzzing. why is it my motor not spinning but make sound.
It sounds like a power supply problem - signal is being sent, but not enough power. How are you powering it? Do the batteries need to be recharged?

And don't double post!!!!!
http://www.societyofrobots.com/robotforum/index.php?topic=3273.0
Title: Re: tms320f2812
Post by: orchid on March 24, 2008, 12:49:10 AM
i am using DC power supply to powering it. now i had another problem. the motor is spinning but not quite well.i want to make a variable speed, control the speed using different frequency. the motor is spinning but not as desired. i am using 1kHz, 3 kHz, 5kHz and 7kHz. it is impossible for the wheelchair to move within the range of the frequency?when i run the source code, the motor spinning but for the 3kHz and 5kHz, the motor's rotation is quite mess. can anyone tell me how to convert the speed from frequency to rpm?

thanks
Title: Re: tms320f2812
Post by: Admin on March 30, 2008, 10:33:38 AM
Quote
can anyone tell me how to convert the speed from frequency to rpm?
You can't, it's impossible. The reason is because speed is dependent on torque, as well.

If estimation isn't good enough, you will need encoders.
Title: Re: tms320f2812
Post by: orchid on March 31, 2008, 07:02:32 PM
thank you admin.
so , how can i estimate the speed by using the variable frequency?
Title: Re: tms320f2812
Post by: Admin on April 06, 2008, 11:22:22 AM
Experiment, graph the results, and write out an equation that represents the graph line.

Use that equation in code . . .
Title: Re: tms320f2812
Post by: orchid on April 07, 2008, 10:13:59 PM
sorry, i did not get it.
can you explain more about it. i don't know which equation i have to use. The source code that i posted before is the commutation states in 3 phase BLDC motor control. i want to make the motor run in the 3 speed, fast,medium,and slow. to do that, i just change the frequency for the commutation states such as

EvaRegs.T1PR =  0x493E;//1kHz (FAST)

EvaRegs.T1PR =  0x30D4;//3kHz (MEDIUM)

EvaRegs.T1PR = 0x1D4C;//5kHz (SLOW)

EvaRegs.T1PR = 0x14ED;//7kHz (SLOW-STOP)

but the commutation states are still the same.

as a result, the motor run but not as expected. can anyone help me how to fix this problem?
thanks....

Title: Re: tms320f2812
Post by: Admin on April 24, 2008, 06:33:43 PM
Quote
can you explain more about it. i don't know which equation i have to use.
open up excel

Send a signal to your motor, measure the speed, record it in excel

Repeat until you have a chart of many speeds vs signal types

Then, using excels' graph function, graph the results using a scatter plot

Then right click the line, and click 'add trendline'. It will give you options on which curve fit you want. Make sure in Options that you select 'Display equation on chart' - that will be your equation which you can put in code.