NXP
Firmware for MC33926 evaluation on KL25Z-based EVB. This works with a Graphical User Interface (GUI) available on NXP.com to control a brushed DC motor using FRDM-33926ESEVM or FRDM-33926PNBEVM. The code enables control of the PWM frequency, duty cycle, enable/disable controls, invert, slew rate control, real-time current monitoring, and includes status flag pin monitoring for undervoltage, short circuit and over-temperature events.
Fork of
Brushed_DC_Motor_Control_MC33926
by 
Travis Alexander
Diff: main.cpp
- Revision:
- 3:d7fd752817e1
- Parent:
- 2:d98eb31a4b69
--- a/main.cpp Mon Jul 09 17:53:48 2018 +0000
+++ b/main.cpp Mon Jul 09 19:23:33 2018 +0000
@@ -8,7 +8,7 @@
// Serial Number: 0x0001
USBHID hid(64, 64, 0x15A2, 0x0138, 0x0001, true);
-//Setup Digital Outputs for the LEDs on the FRDM
+// Setup Digital Outputs for the LEDs on the FRDM
//PwmOut red_led(LED1);
//DigitalOut green_led(LED2);
//DigitalOut blue_led(LED3);
@@ -25,13 +25,13 @@
AnalogIn CFB(PTB0); // Pin FB output from MC33926 to FRDM-KL25Z
//DigitalOut READY(PTC7); // Pin READY input to Motor Control Board (FRDM PIN Name)
-//Variables
+// Variables
int pwm_freq_lo;
int pwm_freq_hi;
int frequencyHz = 500;
int runstop = 0;
int direction = 1;
-int braking; // needs to be initialized?
+int braking; // does not require initialization
int dutycycle = 75;
int newDataFlag = 0;
int status = 0;
@@ -41,7 +41,7 @@
uint16_t CFBAvg;
uint16_t CFBtemp;
-//storage for send and receive data
+// Storage for send and receive data
HID_REPORT send_report;
HID_REPORT recv_report;
@@ -50,13 +50,13 @@
// USB COMMANDS
// These are sent from the PC
#define WRITE_LED 0x20
-#define WRITE_GEN_EN 0x40 // what is this? What should the GUI kickoff here?
+#define WRITE_GEN_EN 0x40
#define WRITE_DUTY_CYCLE 0x50
#define WRITE_PWM_FREQ 0x60
#define WRITE_RUN_STOP 0x70
#define WRITE_DIRECTION 0x71
#define WRITE_BRAKING 0x90
-#define WRITE_RESET 0xA0 // what is this? What should the GUI kickoff here?
+#define WRITE_RESET 0xA0
#define WRITE_D1 0xB1
#define WRITE_EN 0xC1
#define WRITE_D2B 0xD5
@@ -108,38 +108,38 @@
newDataFlag = 1;
if(recv_report.data[1] != 0)
{
- runstop = 1;
+ runstop = 1; // outputs on, run motor
}
else
{
- runstop = 0;
+ runstop = 0; // outputs off, brake motor
}
break;
////////
case WRITE_DIRECTION:
newDataFlag = 1;
- if(recv_report.data[1] == 1) // used to be != 0
+ if(recv_report.data[1] == 1)
{
direction = 1; // corrected allocation for FWD
- //direction = 0; // corrected allocation for REV
+ //direction = 0;
}
else
{
direction = 0; // corrected allocation for REV
- //direction = 1; // corrected allocation for FWD
+ //direction = 1;
}
break;
////////
case WRITE_BRAKING:
newDataFlag = 1;
- if(recv_report.data[1] != 0) // used to be == 1
+ if(recv_report.data[1] != 0)
{
- braking = 1; // this is HS recirc
+ braking = 1; // this is HS recirc
}
else
{
- braking = 0; // this is LS recirc
+ braking = 0; // this is LS recirc
}
break;
////////
@@ -147,11 +147,11 @@
newDataFlag = 1;
if(recv_report.data[1] == 1)
{
- DIS1 = 1; // logic hi will disable the part
+ DIS1 = 1; // logic hi disables the part
}
else
{
- DIS1 = 0; // logic lo will enable the part
+ DIS1 = 0; // logic lo enables the part
}
break;
////////
@@ -159,13 +159,13 @@
newDataFlag = 1;
if(recv_report.data[1] == 1)
{
- //EN = 0; // this is enable case
- EN = 1; // align with the signal being sent from GUI
+ //EN = 0;
+ EN = 1; // logic hi enables the part
}
else
{
- //EN = 1; // this is disable case
- EN = 0; // align with signal being sent from GUI
+ //EN = 1;
+ EN = 0; // logic lo disable the part
}
break;
////////
@@ -173,11 +173,11 @@
newDataFlag = 1;
if(recv_report.data[1] == 1)
{
- D2B = 1;
+ D2B = 1; // logic hi enables the part
}
else
{
- D2B = 0;
+ D2B = 0; // logic lo disables the part
}
break;
@@ -186,11 +186,11 @@
newDataFlag = 1;
if(recv_report.data[1] == 1)
{
- SLEW = 1;
+ SLEW = 1; // logic hi prompts FAST slew
}
else
{
- SLEW = 0;
+ SLEW = 0; // logic lo prompts SLOW slew
}
break;
@@ -199,12 +199,12 @@
newDataFlag = 1;
if(recv_report.data[1] == 1)
{
- INV = 1;
+ INV = 1; // logic hi inverts operation
//INV = 0;
}
else
{
- INV = 0;
+ INV = 0; // logic lo does not invert operation
//INV = 1;
}
break;
@@ -262,15 +262,15 @@
if(braking == 1) //dynamic
{
IN1.period(1/(float)frequencyHz);
- //IN1 = (float)dutycycle/100.0; // this is REV + HS, inverted d
- IN1 = 1.0-((float)dutycycle/100.0); // this is REV + HS
+ //IN1 = (float)dutycycle/100.0; // REV + HS, inverted d
+ IN1 = 1.0-((float)dutycycle/100.0); // REV + HS
IN2 = 1;
}
else //coast
{
- IN1 = 0; // this is REV + LS
+ IN1 = 0;
IN2.period(1/(float)frequencyHz);
- IN2 = (float)dutycycle/100.0;
+ IN2 = (float)dutycycle/100.0; // REV + LS
}
}
else //forward
@@ -279,8 +279,8 @@
{
IN1 = 1;
IN2.period(1/(float)frequencyHz);
- //IN2 = (float)dutycycle/100.0; // this is FWD + HS, inverted d
- IN2 = 1.0-((float)dutycycle/100.0); // this is FWD + HS
+ //IN2 = (float)dutycycle/100.0; // FWD + HS, inverted d
+ IN2 = 1.0-((float)dutycycle/100.0); // FWD + HS
}
else //coast
{
@@ -290,16 +290,16 @@
}
}
}
- else //Stopped
+ else //stopped
{
- if(braking == 1) //braking
+ if(braking == 1) // braking, HS recirc
{
IN1.period(1);
IN2.period(1);
IN1.write(1);
IN2.write(1);
}
- else //coasting
+ else // coasting, LS recirc
{
IN1.period(1);
IN2.period(1);
@@ -311,4 +311,3 @@
}
}
}
-