CCS c PIC getting started

Getting Started with PIC Microcontroller CCS C Compiler CONTENTS PIC16F877A Pin Diagram ………………………………………… TRIS and PORT Registers in PIC Microcontroller ………………… Prerequisite Knowledge …………………………………………… CCS C Discrete IO Functions………………………………… …… get_tris_x()…………………………………………………………… set_tris_x()…………………………………………………………… input_x()……………………………………………………………… output_x()………………………………………………………….… input()……………………………………………………………… output_bit()…………………………………………………………… input_state()……………………………………………… ………… input_change_x()……………………………………… …………… output_float()………………………………………………………… output_drive()………………………………………………………… output_high()………………………………………………………… output_low()………………………………………………….……… output_toggle()……………………………………………….……… Circuit Diagram - LED Blinking……………………….…………… 10 CCS C - Starting a New Project……………………….…….……… 10 CCS C Code - LED Blinking……………………………….….…… 13 You are at the right place if you are a beginner to the field of microcontrollers In this tutorial you will learn How to Blink an LED using PIC Microcontroller PIC is a family of microcontrollers manufactured by Microchip Technology Inc PIC stands for Peripheral Interface Controller It is also referred to as Programmable Interface Controller or Programmable Intelligent Computer As all other microcontrollers PIC Microcontroller can be programmed using Assembly Language As it is little bit difficult we prefer High Level Languages Many high level language compilers are available for programming a PIC Microcontroller like MikroC, MPLAB XC8, Hi-Tech C, CCS C etc In this tutorial we will use CCS C Compiler CCS stands for Custom Computer Services, a Microchip PIC Microcontroller Tool Solutions company MikroC and CCS C are the best compilers for beginners as they includes a lot of built in libraries which enable us to program a PIC Microcontroller without the deep knowledge of its internal architecture I think CCS C is the best High Level Language Compiler for PIC Microcontroller as it is hardware independent In this tutorial we will learn how to write outputs to an IO pin In the following section, I am going to explain the basics of PIC Microcontroller Input Output configurations As we are using CCS C Compiler you may skip it but every PIC programmer should know it In this experiment we are using PIC16F877A microcontroller PIC 16F877A PIN Diagram VDD and VSS are the pins for providing power For PIC 16F877A, VDD = 5V and VSS = GND (0V) Pin 13 & 14, OSC1 and OSC2 are for connecting oscillator which will provide the necessary clock for the operation of microcontroller The 1st pin MCLR is the reset pin of PIC Microcontroller; it is an active low input It should be connected to HIGH (VDD) for normal operations IO (Input Output) pins in a PIC Microcontroller is divided in to different ports, eg : PORTA, PORTB, PORTC, PORTD etc Each PORT is associated with two registers, TRIS and PORT which are named as TRISA, PORTA, TRISB, PORTB etc PORT and TRIS Register in PIC Microcontroller PORT and TRIS are the registers which handle discrete IO operations in PIC Microcontroller TRIS stands for Tri-state TRIS register determines the function of an IO pin Logic at TRIS register makes the corresponding pin Input while Logic at TRIS register makes the corresponding pin Output PORT register can be used to read input pins or to write status of output pins For an Output Pin, Logic at PORT register makes the corresponding pin HIGH state (VDD) while Logic at PORT register makes the corresponding pin LOW state (VSS) Reading PORT register reads the actual voltage levels on IO pins If the actual voltage level is near to HIGH Level (VDD), corresponding PORT bit will be and if the voltage level is near to LOW Level (VSS), corresponding PORT bit will be Hope that you can understand its working from the above image PREREQUISITE KNOWLEDGE  You should know the basics of C Programming for developing projects in CCS C Compiler Following are some C concepts that may help you  A number with a prefix '0b' indicates a binary number  A number with a prefix '0' indicates an octal number  A number with a prefix '0x' indicates a hexadecimal number  A number without prefix is a decimal number Let's see some examples Decimal Binary Octal Hexadecimal 0b00000000 00 0x00 0b00000001 01 0x01 128 0b10000000 0200 0x80 255 0b11111111 0377 0xFF CCS C Discrete IO Functions get_tris_x() This function is used to read TRIS register Examples are given below tris_a = get_tris_A(); //Reads TRISA register tris_b = get_tris_B(); //Reads TRISB register set_tris_x() This function is used to write TRIS register Examples are given below set_tris_b(0xFF); //All pins of PORTB as Input set_tris_c(0x00); //All pins of PORTC as Output input_x() This function is used to read data from an IO port, i.e it returns the value of a PORT register This function sets direction of all pins of the specified port as INPUT (TRIS bits 1) before reading the input Examples are given below a = input_a(); //Reads PORTA b = input_b(); //Reads PORTB c = input_c(); //Reads PORTC output_x() This function is used to write data to a PORT This function sets direction of all pins of specified port as OUTPUT (TRIS bits 0) before writing the output Examples are given below output_b(0xFF); //All pins of PORTB HIGH (VDD) output_c(0x00); //All pins of PORTC LOW (VSS) input() This function returns the state of the specified pin This function sets the direction of the specified pin as INPUT (TRIS bit 1) before reading the input Examples are given below while(!input(PIN_B0)); //Waits for Pin B0 to goes HIGH if(input(PIN_C0)) //Pin C0 is HIGH Now output_bit() This function writes the specified value (1 or 0) to the specified IO pin This function sets the direction of the IO pin to OUTPUT before writing the value output_bit(PIN_B0, 1); //Makes the pin B0 logic HIGH output_bit(PIN_B7, 0); //Makes the pin B7 logic LOW (VSS) (VDD) input_state() This function reads the state of a pin without changing the direction of that pin as input() does b0 = input_state(PIN_B0); //Reads the state of B0 without changing its direction c0 = input_state(PIN_C0); //Reads the state of C0 without changing its direction input_change_x() This function reads the value of the specified port and it compares with the result of last time input_change_x() function was called It returns an bit or a 16 bit number representing the changes on the port A corresponds if the value has changed and corresponds if the value has unchanged portc_check = input_change_c(); output_float() This function sets the specified pin to input mode (TRIS bit 1), which is in high impedance state output_float(PIN_B3); //Makes pin B3 Input output_float(PIN_C5); //Makes pin C5 Input output_drive() This function sets the specified pin to output mode (TRIS bit 0) output_drive(PIN_B6); //Makes pin B6 output output_drive(PIN_C3); //Makes pin C3 output output_high() This function sets the specified pin to HIGH state (VDD) output_high(PIN_A0); //Makes pin A0 HIGH output_high(PIN_E0); //Makes pin E0 HIGH output_low() This function sets the specified pin to LOW state (VSS) output_low(PIN_A2); //Makes pin A2 LOW output_low(PIN_E1); //Makes pin E1 LOW output_toggle() This function toggles the HIGH/LOW state of the specified pin output_toggle(PIN_B1); output_toggle(PIN_B2); //Toggles the state of //Toggles the state of PIN B2 PIN B1 Circuit Diagram - LED Blinking Blinking LED using PIC Microcontroller - Circuit Diagram CCS C - Starting a New Project Hope you download CCS C compiler from CCS Website and installed it  Open the CCS C Software  CCS C Compiler 10  File >> New >> Project Wizard  Opening New Project Wizard  Name the Project 11  Project Wizard - Save Project As  Select the device and Set Clock frequency  Project Wizard - Select Device and Set Clock Frequency  Click on Create Project  The New Project Wizard is completed, now you can see code editor  Enter the Code 12 CCS C Code - LED Blinking #include #use delay (clock=8000000) void main() { while(TRUE) { output_high(PIN_B0); //LED ON delay_ms(1000); //1 Second Delay output_low(PIN_B0); //LED OFF delay_ms(1000); //1 Second Delay } Enter the Code Here - CCS C Editor d     Then click on Compile This will generate, hex file in your project folder This is the file that to be burned to PIC Microcontroller You can also simulate its working in Proteus ISIS 13 ... LED using PIC Microcontroller - Circuit Diagram CCS C - Starting a New Project Hope you download CCS C compiler from CCS Website and installed it  Open the CCS C Software  CCS C Compiler 10... will use CCS C Compiler CCS stands for Custom Computer Services, a Microchip PIC Microcontroller Tool Solutions company MikroC and CCS C are the best compilers for beginners as they includes a... Clock Frequency  Click on Create Project  The New Project Wizard is completed, now you can see code editor  Enter the Code 12 CCS C Code - LED Blinking #include #use delay (clock=8000000)