Elijah Stanger-Jones / Mbed OS motor_shield_example

An example code for using the motorshield for 2.74

Dependencies:   QEI_pmw MotorShield

main.cpp@3:1eee0d9f1223, 2020-09-12 (annotated)

Committer:
elijahsj
Date:
Sat Sep 12 17:12:04 2020 +0000
Revision:
3:1eee0d9f1223
Parent:
2:358bdcaaf496 
Fixed types

Who changed what in which revision?

UserRevisionLine numberNew contents of line
elijahsj 0:92642f80db7c 1 #include "mbed.h"
elijahsj 0:92642f80db7c 2 #include "rtos.h"
elijahsj 0:92642f80db7c 3 #include "QEI.h"
elijahsj 0:92642f80db7c 4 #include "MotorShield.h"
elijahsj 0:92642f80db7c 5 #include "HardwareSetup.h"
elijahsj 0:92642f80db7c 6
elijahsj 0:92642f80db7c 7 Serial pc(USBTX, USBRX); // USB Serial Terminal
elijahsj 0:92642f80db7c 8 Timer t; // Timer to measure elapsed time of experiment
elijahsj 0:92642f80db7c 9
elijahsj 0:92642f80db7c 10 QEI encoderA(PE_9,PE_11, NC, 1200, QEI::X4_ENCODING); // MOTOR A ENCODER (no index, 1200 counts/rev, Quadrature encoding)
elijahsj 0:92642f80db7c 11 QEI encoderB(PA_5, PB_3, NC, 1200, QEI::X4_ENCODING); // MOTOR B ENCODER (no index, 1200 counts/rev, Quadrature encoding)
elijahsj 0:92642f80db7c 12 QEI encoderC(PC_6, PC_7, NC, 1200, QEI::X4_ENCODING); // MOTOR C ENCODER (no index, 1200 counts/rev, Quadrature encoding)
elijahsj 0:92642f80db7c 13 QEI encoderD(PD_12, PD_13, NC, 1200, QEI::X4_ENCODING);// MOTOR D ENCODER (no index, 1200 counts/rev, Quadrature encoding)
elijahsj 0:92642f80db7c 14
elijahsj 0:92642f80db7c 15 MotorShield motorShield(12000); //initialize the motor shield with a PWM period of 12000 ticks or ~20kHZ
elijahsj 0:92642f80db7c 16
elijahsj 0:92642f80db7c 17 int main (void)
elijahsj 0:92642f80db7c 18 {
elijahsj 0:92642f80db7c 19 // Setup experiment
elijahsj 0:92642f80db7c 20 t.reset();
elijahsj 0:92642f80db7c 21 t.start();
elijahsj 0:92642f80db7c 22 encoderA.reset();
elijahsj 3:1eee0d9f1223 23 float position;
elijahsj 3:1eee0d9f1223 24 float velocity;
elijahsj 3:1eee0d9f1223 25 float current;
elijahsj 1:7811196d1a57 26 motorShield.motorAWrite(0, 0); //turn motor A off
elijahsj 1:7811196d1a57 27
elijahsj 1:7811196d1a57 28 //use the motor shield as follows:
elijahsj 1:7811196d1a57 29 //motorShield.motorAWrite(DUTY CYCLE, DIRECTION), DIRECTION = 0 is forward, DIRECTION =1 is backwards.
elijahsj 0:92642f80db7c 30
elijahsj 0:92642f80db7c 31 // Run experiment for 10 seconds
elijahsj 0:92642f80db7c 32 while( t.read() < 10 ) {
elijahsj 0:92642f80db7c 33 // Perform control loop logic
elijahsj 0:92642f80db7c 34 if (t.read() < 5)
elijahsj 0:92642f80db7c 35 motorShield.motorAWrite(0.5, 0); //run motor A at 50% duty cycle and in the forward direction for 5 seconds
elijahsj 0:92642f80db7c 36 else
elijahsj 0:92642f80db7c 37 motorShield.motorAWrite(0.5, 1); //run motor A at 50% duty cycle and in the reverse direction for 5 seconds
elijahsj 0:92642f80db7c 38
elijahsj 2:358bdcaaf496 39 position = 0; //MODIFY THIS
elijahsj 2:358bdcaaf496 40 velocity = 0; //MODIFY THIS
elijahsj 2:358bdcaaf496 41 current = motorShield.readCurrentA()*(30.0/65536.0)-15; //read current for motor A in amps. Note: this is a slightly different current sensor so its a different conversion than last lab.
elijahsj 0:92642f80db7c 42
elijahsj 3:1eee0d9f1223 43 pc.printf("Current reading: %f Amps, Velocity: %f, Angle: %f \n\r", current, velocity, position);
elijahsj 0:92642f80db7c 44
elijahsj 1:7811196d1a57 45 wait(.01); //run control loop at 100Hz
elijahsj 0:92642f80db7c 46 }
elijahsj 0:92642f80db7c 47
elijahsj 0:92642f80db7c 48 motorShield.motorAWrite(0, 0); //turn motor A off
elijahsj 0:92642f80db7c 49
elijahsj 0:92642f80db7c 50 while(1) {
elijahsj 0:92642f80db7c 51 //loop forever
elijahsj 0:92642f80db7c 52 }
elijahsj 0:92642f80db7c 53
elijahsj 0:92642f80db7c 54 } // end main