Difference between revisions of "PIC32MX: Digital Outputs"
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Working with digital inputs and outputs is fundamental to circuit design, and PIC microcontrollers add versatility to design by allowing programming and re-programming of the logic associated with input and output pins. In this way, one PIC microcontroller can take the place of many pre-programmed digital logic ICs. |
Working with digital inputs and outputs is fundamental to circuit design, and PIC microcontrollers add versatility to design by allowing programming and re-programming of the logic associated with input and output pins. In this way, one PIC microcontroller can take the place of many pre-programmed digital logic ICs. |
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==Available Pins== |
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<br><br> |
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==Digital Output Example== |
==Digital Output Example== |
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This section describes how to set up and write digital outputs using a PIC32MX460F512L. |
This section describes how to set up and write digital outputs using a PIC32MX460F512L. |
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===Sample Code=== |
===Sample Code=== |
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Program to turn on LEDs based on User Switch of |
Program to turn on LEDs based on User Switch of NU32. swUser must be defined for a switch [[PIC32MX460F512L : Digital Inputs |(digital input) ]] if not using NU32. |
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/******************************************************************** |
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First include header files with definitions for generic type definitions, compiler, and for specific PIC. Also include the plib header file. |
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Super simple Digital Output. |
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********************************************************************/ |
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#include "HardwareProfile.h" |
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// NOTE THAT BECAUSE WE USE THE BOOTLOADER, NO CONFIGURATION IS NECESSARY |
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// THE BOOTLOADER PROJECT ACTUALLY CONTROLS ALL OF OUR CONFIG BITS |
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// Define constants for PINS D1 - D4 |
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#define PIN_D1 LATDbits.LATD1 |
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#define PIN_D2 LATDbits.LATD2 |
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#define PIN_D3 LATDbits.LATD3 |
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#define PIN_D4 LATDbits.LATD4 |
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int main(void) |
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{ |
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// Set all analog pins to be digital I/O |
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// This line of code only needs to be used if your pins are Analog Input (B port) |
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AD1PCFG = 0xFFFF; |
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// Configure the proper PB frequency and the number of wait states |
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SYSTEMConfigPerformance(SYS_FREQ); |
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//Set D1, D2, D3, and D4 as a digital output |
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LATD |= 0x001E; TRISD &= 0xFFE1; |
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while(1) |
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{ |
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if(swUser) |
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{ |
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PIN_D1 = 1; |
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PIN_D2 = 0; |
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PIN_D3 = 1; |
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PIN_D4 = 0; |
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} |
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else |
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{ |
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PIN_D1 = 0; |
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PIN_D2 = 1; |
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PIN_D3 = 0; |
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PIN_D4 = 1; |
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} |
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} |
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} |
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#include "GenericTypeDefs.h" |
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#include "Compiler.h" |
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#include "HardwareProfile.h" |
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#include <plib.h> |
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NOTE THAT BECAUSE WE USE THE BOOTLOADER, NO CONFIGURATION IS NECESSARY. THE BOOTLOADER PROJECT ACTUALLY CONTROLS ALL OF OUR CONFIG BITS. |
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Define a constants for 4 output pins. LATx is the function used to write to a pin. |
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#define PIN_D4 LATDbits.LATD4 |
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#define PIN_D5 LATDbits.LATD5 |
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#define PIN_D6 LATDbits.LATD6 |
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#define PIN_D7 LATDbits.LATD7 |
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Begin main body of program. |
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int main(void){ |
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Configure the proper PB frequency and number of wait states in this case 80MHz. |
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SYSTEMConfigPerformance(80000000L); |
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Set all analog pins to be digital I/O |
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AD1PCFG = 0xFFFF; |
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Turn off JTAG so we get the pins back |
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mJTAGPortEnable(0); |
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The pins that we want to use as outputs must be initialized as an outputs. TRISx is a register that sets the pin as an input (1) or an output(0). You can set entire ports as inputs / outputs by using TRISX &= Hex number; We use &= hex number to only change the pins that we want to set as inputs / outputs. |
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Set D4, D5, D6, and D7 as a digital outputs |
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LATD |= 0x00F0; TRISD &= 0xFF0F; |
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Use while to set up infinite loop. What we're going to do is blink LEDs on the board on and off depending on whether the user switch is pressed. |
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while(1) |
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{ |
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if(swUser) |
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{ |
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PIN_D4 = 1; |
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PIN_D5 = 0; |
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PIN_D6 = 1; |
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PIN_D7 = 0; |
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} |
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else |
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{ |
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PIN_D4 = 0; |
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PIN_D5 = 1; |
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PIN_D6 = 0; |
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PIN_D7 = 1; |
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} |
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} |
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} // end main |
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<br> |
<br> |
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Revision as of 14:40, 5 January 2010
Working with digital inputs and outputs is fundamental to circuit design, and PIC microcontrollers add versatility to design by allowing programming and re-programming of the logic associated with input and output pins. In this way, one PIC microcontroller can take the place of many pre-programmed digital logic ICs.
Digital Output Example
This section describes how to set up and write digital outputs using a PIC32MX460F512L.
Sample Code
Program to turn on LEDs based on User Switch of NU32. swUser must be defined for a switch (digital input) if not using NU32.
/********************************************************************
Super simple Digital Output.
********************************************************************/
#include "HardwareProfile.h"
// NOTE THAT BECAUSE WE USE THE BOOTLOADER, NO CONFIGURATION IS NECESSARY
// THE BOOTLOADER PROJECT ACTUALLY CONTROLS ALL OF OUR CONFIG BITS
// Define constants for PINS D1 - D4
#define PIN_D1 LATDbits.LATD1
#define PIN_D2 LATDbits.LATD2
#define PIN_D3 LATDbits.LATD3
#define PIN_D4 LATDbits.LATD4
int main(void)
{
// Set all analog pins to be digital I/O
// This line of code only needs to be used if your pins are Analog Input (B port)
AD1PCFG = 0xFFFF;
// Configure the proper PB frequency and the number of wait states
SYSTEMConfigPerformance(SYS_FREQ);
//Set D1, D2, D3, and D4 as a digital output
LATD |= 0x001E; TRISD &= 0xFFE1;
while(1)
{
if(swUser)
{
PIN_D1 = 1;
PIN_D2 = 0;
PIN_D3 = 1;
PIN_D4 = 0;
}
else
{
PIN_D1 = 0;
PIN_D2 = 1;
PIN_D3 = 0;
PIN_D4 = 1;
}
}
}
