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ressas
Joined: 15 Nov 2019 Posts: 135
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PWM1 AND PWM2 with 18f46k22[SOLVED] |
Posted: Thu Sep 17, 2020 6:06 am |
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Hello to everyone.
I'm trying to write some code for the H bridge.
I design the H bridge myself. I control 4 IRLZ44NS at 12V by giving 12 volts to the GATE. I'm checking the Gate with 4 mmbt2222 npn transistors. When I start normally, the engine is controlled.
Code: |
//for up
void UP(void){
output_high(M2c2);
output_low(M1c3);
output_low(M4c0);
output_high(M3c1);
}
//for down
void down(void){
output_high(M1c3);
output_low(M2c2);
output_low(M3c1);
output_high(M4c0);
}
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But when I trigger it with pwm, only my DOWN Function works fine.
But in my UP Function; power supply switches to high current fault. Do you think why?
Code: |
#include <18f46k22.h>
#INCLUDE <stdlib.h>
#fuses INTRC_IO,NOWDT,NOBROWNOUT,NOPUT,NOWRT,NODEBUG, NOMCLR, NOPROTECT, NOWDT, NOLVP, PLLEN
#use delay(clock=64000000) //osilatör frekansı 4Mhz'e ayarlandı
#use rs232(baud=9600,parity=N,xmit=PIN_C6,rcv=PIN_C7,bits=8)
#define M4c0 pin_c0
#define M3c1 pin_c1
#define M2c2 pin_c2
#define M1c3 pin_c3
void down(void);
void Up(void);
void main ( )
{
output_c(0x0C);
delay_ms(1000);
setup_ccp1(CCP_PWM);
setup_ccp2(CCP_PWM);
setup_timer_2(T2_DIV_BY_16,100,16);
set_pwm1_duty(25); // M4C0
set_pwm2_duty(25); // M3C1
while(true)
{
UP();
}
}
void UP(void){ // it is not work
output_high(M2c2);
output_low(M1c3);
// output_low(M4c0);
output_high(M3c1);
set_pwm2_duty(0); // M3C1
set_pwm1_duty(25); // M4C0
}
void down(void){ it is work
output_high(M1c3);
output_low(M2c2);
//output_low(M3c1);
output_high(M4c0);
set_pwm1_duty(0); // M4C0
set_pwm2_duty(25); // M3C1
}
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Last edited by ressas on Thu Oct 08, 2020 10:49 pm; edited 1 time in total |
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temtronic
Joined: 01 Jul 2010 Posts: 9226 Location: Greensville,Ontario
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Posted: Thu Sep 17, 2020 6:13 am |
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Could be a simple wiring mistake, or turning on the wrong drivers.....
Instead of ...
#define M4c0 pin_c0
#define M3c1 pin_c1
#define M2c2 pin_c2
#define M1c3 pin_c3
I'd code so the defines 'show' what leg or arm of the Hbridge they control.
say 'UL' for Upper Left, 'UR' for Upper Right, 'LL' for Lower Left, and 'LR' for Lower Right'.
This way you can see what gets turned on and off.
If you have more than one motor,...M1UL = Motor number 1, Upper Left.
Jay |
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ressas
Joined: 15 Nov 2019 Posts: 135
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Posted: Thu Sep 17, 2020 6:15 am |
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temtronic wrote: | Could be a simple wiring mistake, or turning on the wrong drivers.....
Instead of ...
#define M4c0 pin_c0
#define M3c1 pin_c1
#define M2c2 pin_c2
#define M1c3 pin_c3
I'd code so the defines 'show' what leg or arm of the Hbridge they control.
say 'UL' for Upper Left, 'UR' for Upper Right, 'LL' for Lower Left, and 'LR' for Lower Right'.
This way you can see what gets turned on and off.
If you have more than one motor,...M1UL = Motor number 1, Upper Left.
Jay |
nice suggestion thanks
#define DR pin_c0
#define DL pin_c1
#define UR pin_c2
#define UL pin_c3 |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19513
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Posted: Thu Sep 17, 2020 7:14 am |
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I don't see in what you post, any sign that you are setting the second PWM to
use that pin. You need the fuse CCP2C1. It may well be going to B3.... |
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ressas
Joined: 15 Nov 2019 Posts: 135
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Posted: Thu Sep 17, 2020 7:39 am |
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Ttelmah wrote: | I don't see in what you post, any sign that you are setting the second PWM to
use that pin. You need the fuse CCP2C1. It may well be going to B3.... |
I add this fuse but; not work
I think the problem is not caused by cc2 but by ccp1.
My problem isn't just that pwm isn't working.
Also, when I use "set_pwm1_duty", high current is also drawn. |
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ressas
Joined: 15 Nov 2019 Posts: 135
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Posted: Thu Sep 17, 2020 7:59 am |
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AND
Not because the motor draws high current.
I did not connect the motor and continued to give high current warning I guess I can't really trigger the mosfets.
AND why? |
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alan
Joined: 12 Nov 2012 Posts: 357 Location: South Africa
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Posted: Thu Sep 17, 2020 8:40 am |
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Maybe post a schematic, might be a wiring problem |
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temtronic
Joined: 01 Jul 2010 Posts: 9226 Location: Greensville,Ontario
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Posted: Thu Sep 17, 2020 9:44 am |
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Have to ask WHAT gives you the 'high current' warning ?
also
If it is drawing current without the motor, that suggests both upper and low MOSFETs are on, effectively a power supply short.....
Jay |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19513
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Posted: Thu Sep 17, 2020 10:33 am |
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Two things:
This line:
setup_timer_2(T2_DIV_BY_16,100,16);
Sets the PWM to 9.9KHz. I guess you want 10K?. If so you need to use
99 for PR2. Remember the division is PR2+1.
Post what MOSFET is connected where?. When you are operating the
circuit 'yourself', you turn on C0 and C3 or C2 and C3, but with the PWM
you are turning on C2 and C1. Very different.... |
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ressas
Joined: 15 Nov 2019 Posts: 135
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Posted: Fri Sep 18, 2020 5:55 am |
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Ttelmah wrote: | Two things:
Post what MOSFET is connected where?. When you are operating the
circuit 'yourself', you turn on C0 and C3 or C2 and C3, but with the PWM
you are turning on C2 and C1. Very different.... |
Yes Ttelmah. you are very different.
Thank you.
This solved my problem.
However, I used an outside interrupt to stop the engine.
After using this interrupt I got an error like this:
interrupts disabled during call to prevent reentrancy (@ADDF)
Actually, as this is a separate problem, you may not be able to answer that. I think I should investigate some things myself.
However, there is something that surprises me. On page 21 of the datasheet, pwm1 property for c0 and c2 appears.
Why can't I use it in C0?
You can view the scheme of the H bridge here:
https://ibb.co/Y381cX3
AND
Quote: |
Have to ask WHAT gives you the 'high current' warning ?
also
If it is drawing current without the motor, that suggests both upper and low MOSFETs are on, effectively a power supply short.....
Jay |
Yes Temtronic. You are right. That was exactly the problem |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19513
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Posted: Fri Sep 18, 2020 7:05 am |
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Two separate things here.
The first is down to the mode you run the PWM.
In standard mode (CCP_PWM), it only generates the single signal on PWMx.
In it's enhanced mode, you have four PWM outputs from each PWM, and these
go to P1A, P1B, P1C & P1D. The signals from these can be 'steered' to
different pins, or used as half bridge or full bridge pairs. The pulse steering
is done using the settings CCP_PULSE_STEERING_x in the CCP setup. Where
'x' is the output you want to use (A, B, C or D).
However the second part here is an error in the data sheet. C0, is P2B,
which is the 'B' output from PWM2, not from PWM1. The title is right in
the pin names, but wrong in the description. So you can't use this for PWM1...
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ressas
Joined: 15 Nov 2019 Posts: 135
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Posted: Fri Sep 18, 2020 8:11 am |
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Ttelmah wrote: |
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Get it.
Don't be sad |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19513
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Posted: Fri Sep 18, 2020 10:59 am |
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I always hate it when a data sheet is wrong...
On the interrupts disabled warning, this means you are using the same
function both inside and outside the interrupt. To avoid this being
therefore being called 'inside itself', the version outside the interrupt
gets the interrupts disabled around it, and you get this warning.
For anything reasonably 'quick', don't worry about it. |
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jeremiah
Joined: 20 Jul 2010 Posts: 1349
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Posted: Fri Sep 18, 2020 5:47 pm |
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Is the F in ADDF "float" or is that some sort of bank notation? I'm used to PIC24's and don't know the PIC18's. If it is for floats, then I would recommend not doing float math in an ISR. |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19513
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Posted: Sat Sep 19, 2020 12:10 am |
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Don't know.
On my PIC24 code, the float addition is called ADDFF & ADDFF64 (for the
double version). I don't get an ADDF. Have looked through half a dozen
programs. Would agree wholeheartedly. It might be being triggered
accidentally if a variable type is float, and it is used for something quite
#innocent' like array indexing.... |
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