db66dev1_debug_demo/main.c

===== Description =====

This demo shows how to:

• Read the value of a potentiometer connected to an analog input
• Read buttons and control LEDs on the DB66DEV1 development board (using DB66DEV1 driver located in nz_db66dev1.h)
• Output a frequency with varying duty cycles to a PWM channel. The PWM output is connected to a buzzer, and the duty cycle is used to set the volume.

This demo uses a DB66DEV1 development daughter board. It has 4 buttons, 8 LEDs, a potentiometer and a buzzer.

The potentiometer is used to set the frequency of the buzzer to a value between 255 to 2795 Hz.

Buttons 1 and 2 are used to set the volume to a level between 0 to 8. The volume is represented on the LEDs, with volume 0=all LEDs of, and volume 8 all LEDs on.

The PWM duty cycle is set to a value between 0 to 0.33 depending on the current volume setting.

Additionally this demo also implements debugging via the USB port and the Netcruzer USB Terminal App. During the program various debug messages are written, which will be displayed on the "Netcruzer USB Terminal" (running on a PC connected to the target board's USB port). This demo also monitors the USB port for Debug messages send to us.
- If "hi" is received, it replies with "Hello"
- If "adc" is received, it replies with the analog value of the potentiometer
Use the "Netcruzer USB Terminal" App to send and receive USB Debug messages. It can be downloaded here: https://netcruzer.com/usbterminal/

===== Required Hardware =====

The project requires a SBC66 Netcruzer board with an USB Port (not USB Host), AND a DB66DEV1 development board. The DB66DEV1 is plugged into the daughter board connector of the SBC66 board.

===== Building Project =====

This project is located in the "src/demos/db66dev1/db66dev1_debug_demo" folder of the Netcruzer Download. To compile for Netcruzer Board, open this project in MPLAB X, and select the "Project Configuration" for desired board. For example "SBC66ZL_R1" for the SBC66ZL Revision 1 board. For details click here

===== Programming Board =====

After compiling (build), the board can be programmed via the USB Bootloader or a PIC Programmer. USB Programming is simplified when using the SBC board together with a Prototype Board.

===== File History =====

2013-07-22, David H. (DH):

• Initial version

#define THIS_IS_MAIN_FILE   //Uniquely identifies this as the file with the main application entry function main()

// Includes /////////////////////////////////////
#include "HardwareProfile.h"    //Required for all Netcruzer projects
#include "nz_db66dev1.h"

//Add debugging. DEBUG_CONF_MAIN macro sets debugging to desired level (defined in projdefs.h)
#if !defined(DEBUG_CONF_MAIN)
    #define DEBUG_CONF_MAIN     DEBUG_CONF_DEFAULT   //Default Debug Level, disabled if DEBUG_LEVEL_ALLOFF defined, else DEBUG_LEVEL_ERROR
#endif
#define MY_DEBUG_LEVEL   DEBUG_CONF_MAIN
#include "nz_debug.h"

// Variables ////////////////////////////////////
static WORD potValue = 0, newPotValue = 0;
static BYTE volume = 0, newVolume = 0;
static BYTE buttons;
static WORD tmrFlashLed = 0;        //Timer for flashing system LED
static WORD tmrServiceDB66DEV1 = 0; //Timer for checking button and Potentiometer inputs


int main(void) {

    //Default initialization. All ports inputs. All analog features disabled. Tick 1ms
    nzSysInitDefault();

    DEBUG_PUT_STR(DEBUG_LEVEL_INFO, "\nThis is a test debug message from db66dev1 demo");

    DIR_SYSLED = OUTPUT_PIN;    //Set System LED port as outputs

    //Initialize DB66DEV1, all LEDs are output and turned off, Buttons inputs
    db66dev1_Init();

    //Configure port 3 (old port name X3) as ADC channel, is connected to Potentiometer on DB66DEV1
    adcOpen(ADC_OPEN_A3);

    //Congigure port 30 (old port name Y4) (Buzzer on DB66DEV1) as PWM channel 1. 
    pwm1OpenDefault(PPS_OUT_34, 0);

    //Main loop
    while(1)
    {
        nzSysTaskDefault();     //Main netcruzer task, call in main loop.

        //Service DB66DEV1 every 10ms
        if (tick16TestTmr(tmrServiceDB66DEV1)) {
            tick16UpdateTmrMS(tmrServiceDB66DEV1, 10);   //Update timer to expire in 10ms again

            db66dev1_Service();     //DB66DEV1 service routine. Must be called each 10ms (default, can be changed)

            //Get latched button value. This function will clear the latched value of all buttons!
            buttons = db66dev1_ReadLatchedButtons();

            //Was button 2 pressed, increase volume
            if(buttons & 0x02) {
                //Increase volume, maximum level is 8
                if (newVolume < 8)
                    newVolume++;
            }
            //Was button 1 pressed, decrease volume
            if(buttons & 0x01) {
                //Decrease volume, minimum level is 0
                if (newVolume != 0)
                    newVolume--;
            }

            //Get the potentiometer analog input, will be a value from 0 to 255
            newPotValue = adcReadChan8BitForIndex(0);    //Use index function

            //Only enter if volume of potentiometer value has changed
            if ( (potValue!=newPotValue) || (newVolume!=volume) ) {
                WORD pwmPeriod;
                float dcRatio;      //Duty Cycle ratio
                potValue = newPotValue;
                volume = newVolume;

                //Update LEDs with new volume level.
                //For volume=0, all LEDs are off, for volume=8 all LEDS are on
                db66dev1_WriteLeds(0xff >> (8-volume));

                //Calculate period with forumula: 0xffff - (potValue * 250) <br>
                //This gives a range of 1785 to 65535, which gives a frequency range
                //of 244 to 8963Hz. For pwmSetPeriod(), the frequency is calculated:
                //PWM Frequency = 16000000 / (period+1)
                pwmPeriod = 0xffff - (potValue * 250);
                pwmSetPeriod(1, pwmPeriod);                     //Set PWM1 period with calculated value
                dcRatio = (((float)(volume*volume)) / 192.0);   //Duty cycle range from 0 to 0.33 (volume*volume gives exponential curve)
                pwmSetDutyCycle(1,((float)pwmPeriod)*dcRatio);  //Set duty cycle to 25% (one quarter)
                printf("\nSetting f=%.0fHz and dc=%.2f", (double)pwmGetFrequency(1), (double)dcRatio);  //Print frequency and duty cycle to Debug Terminal

                //ALTERNATIVE METHOD, COMMENTED BY DEFAULT!
                //Set frequency and duty cycle.
                //Frequency can have a minimum value of 245. Range is 245 to 2795 Hz
                //Duty cycle has a range from 0 to 0.33. Use exponential curve (volume*volume)
                //pwmSetFreqAndDutyCycle(1, (newPotValue*10)+245, dcRatio );
                //printf("\nSetting f=%uHz and dc=%.2f", (newPotValue*10)+245, dcRatio);  //Print frequency and duty cycle to Debug Terminal
            }
        }

        //Flash system LED every 500ms
        if (tick16TestTmr(tmrFlashLed)) {
            tick16UpdateTmrMS(tmrFlashLed, 100); //Update timer to expire in 10ms again
            LAT_SYSLED = !LAT_SYSLED;       //Toggle System LED
        }
    }//end while
}

#if defined(HAS_NZ_DEBUGGING)

void debugService(void) {
    //Check if a debug message was received
    if (cbufHasWholePacket(CIRBUF_RX_DEBUG)) {
        //'hi' - Reply with "Hello" on a new line
        if (cbufPacketStrcmp(CIRBUF_RX_DEBUG, "hi") == 0) {
            debugPutString("\nHello");
        }
        //"adc' - Print Potentiometer ADC value
        else if (cbufPacketStrcmp(CIRBUF_RX_DEBUG, "adc") == 0) {
            debugPutString("\nADC = ");
            debugPutWord(adcReadChan8BitForIndex(0));
            //printf("\nADC = %d", adcReadChan8BitForIndex(0));  //Alternative method
        }

        //Remove received packet. If it was not processed above, it is lost!
        cbufRemovePacket(CIRBUF_RX_DEBUG);
    }
}
#endif