Yes, you are correct. A good way to do it would be to power the processor with an LM7805 (LM340T-5) linear regulator with suitable heat sink. A better but more complex way would be to use one of the simple-switcher setups. A switcher won't waste the battery power like the linear regulator will. To regulate, the linear one dissipates the extra power as heat - wasting it, the switcher turns off/on at high frequency to maintain a uniform output. The link has a calculator that figures things out for you. Nice.
Are you sure you have enough capacity in your power supply? Adequate wire sizes. IIRC, you are going for 8A on the motors. That's a bunch.
(I have tested it). Ratings say that it can provide about 113A continuously. . Could that also be a factor? I mean..it works well with LEDs(gradually brightens up and dims out). I guess timers will simplify this program...but I don't know the code for that...The program increases voltage on pin P2.0 when p0.0 is 0 and p0.1 is 1 and vice versa; and holds the current voltage when both pins are either high or low. Here is the code:
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#include<reg52.h>
#include<stdio.h>
void delay(void);
sbit motor_pin_1 = P2^0;
sbit switch_st=P1^1;
sbit switch_st2=P1^0;
bit x;
bit y;
void hold(int v,int l)
{
int i;
do
{
x=switch_st;
y=switch_st2;
motor_pin_1=1;
for(i=0;i<=v;i++)
{
delay();
}
motor_pin_1=0;
for(i=l;i>=v;i--)
{
delay();
}
}while((x==0&&y==0)||(x==1&&y==1));
}
int increase(int l,int v)
{
int c=v,i;
do
{
x=switch_st;
y=switch_st2;
motor_pin_1=1;
for(i=0;i<=c;i++)
{
delay();
}
motor_pin_1=0;
for(i=l;i>=c;i--)
{
delay();
}
if(c<=500)
c++;
}while(x==1&&y==0);
return c;
}
int decrease(int l,int v)
{
int c=v,i;
do
{
y=switch_st2;
x=switch_st;
motor_pin_1=1;
for(i=0;i<=c;i++)
{
delay();
}
motor_pin_1=0;
for(i=l;i>=c;i--)
{
delay();
}
if(c>=0)
c--;
}while(y==1&&x==0);
return c;
}
void delay()
{
int i;
for(i=0;i<10;i++)
{
}
}
void main()
{
int v=0;
switch_st=1;
switch_st2=1;
motor_pin_1=0;
do
{
x=switch_st;
y=switch_st2;
if(x==1&&y==0)
{
v=increase(500,v);
}
else
{
if(y==1&&x==0)
v=decrease(500,v);
if((x==0&&y==0)||(x==1&&y==1))
hold(v,500);
}
}while(1);
}
I have tried this before. Its working.
The uC connected to the driver circuit is working exactly like I want it to even when I load the motor(8A current). This set-up is working even on a breadboard(but its starting to melt, which is obvious). If high current was the issue...would the motor run as per circuit even without the RF?The uC with the driver circuit is working well. However when I use the RF module to drive the input of the uC, the circuit isnt working. I think its the Rf module thats getting affected by the noise rather than the uC. I say this because the enable pin of the decoder IC, that is supposed to go high when receiving from the transmitter(the encoder IC eventually), goes low as soon as the motor starts for the first time. It stays low until power to motor is reset by disconnecting motor/wires.
I have only a basic multi-meter with voltage, current and resistance functions.
In that case, I would suspect that motor noise (arcing from the brushes to the commutator), radiated or conducted, is the likely problem. Can you visually see any blue sparking when the motor runs?
1) Reducing or eliminating sparking would be a good thing. I searched on 'how to reduce commutator arcing' and got some good info including a thread here on AAC. This and this and this may shed some light on particular values to try. I'd just be guessing. You might try just wrapping the motor in aluminum foil like a big tamale to see if some shielding helps. Try grounding the foil to an earth ground.
