AVR DDS signal generator V1. Sometimes when tuning various electronic hardware we need simple signal generator with various waveform and frequency. One of the options is to by a professional with variable gain professional coating and many additional functions. But if you are an amateur you might want to build one. This small project is dedicated for building one of those signal generators. Specification. AVR DDS signal generator consists of following parts Atmel Atmega. Supply source and voltage regulator 21. Shots/complete.png' alt='Avr Simulator Software Free Download' title='Avr Simulator Software Free Download' />RTOS FreeRTOS is a truly free professional grade RTOS for microcontrollers that supports 35 MCU architectures and become a market leader. A Portable, open source. EPanorama Software and tools section. The Hardware Book v1. The Hardware Book contains miscellaneous technical information about computers and other electronic. The AVR Toolchain is a collection of toolslibraries used to create applications for AVR microcontrollers. This collection includes compiler, assembler, linker and. A Quickstart Tutorial for ATMEL AVR Microcontrollers. If youre at all like me, you learn best by example and by doing. If that also sounds like you and youre. MPLAB IDE, Free Download by Microchip Technology Inc. PIC usually pronounced as pick is a family of microcontrollers made by Microchip Technology, derived from the PIC1650 originally developed by General Instruments. HhvDwDl9Y/T2RXwVCulCI/AAAAAAAAABY/PhDzZ7CSBr8/s1600/dc-voltmeter-circuit-diagram.jpg' alt='Avr Simulator Software Free Download' title='Avr Simulator Software Free Download' />LCD and shift register 7. HC1. 64 7 buttons R 2. R resistor leader for DAC Three outputs universalOUT from DAC, PWM and pulses Metal case and microcontroller firmware. Atmega. 8 microcontroller is a simplest of atmega series. There is 8kb of FLASH program memory, maximum frequency is 1. MHz, which is used to reach DDS generators maximum resolution at maximum frequency. For know frequency is limited from 1 to 6. Hz with minimal step of 1. Hz. DDS AVR generator is powered with 9. V battery. Voltage is reduces to 5. V and stabilized by 7. LCD is controlled using three wires through shift register 7. HC1. 64. So this register is used as serial to parallel converter in order to save microcontroller pins. LCD is controlled in 8 bit mode. AVR DDS Generator uses 7 control buttons Start Stop, which is a reset also IP increasing value DOWN decreasing value Mode. Mode. 2 signal properties Freq signal frequency multiplier selection. Buttons on the box AVR DDS signal generator uses R 2. R digital to analog DAC converter This is a simplest solution where resistors are connected in a ladder In this schematic R1. Adobe Photoshop Cs3 Free Tutorials For Beginners Pdf. By using 8 bits and 5. V step value is about 1. V. This is enough for getting average quality signals. Generator has three outputs Universal DAC output through R 2. R ladder PWM Impulse SQ Universal output OUT is a signal output from DAC. This output is to form various signals like sawtooth, sine, square, triangle. PWM channel is used to form for PWM signal output directly from timer. SQ channel is additional channel to form square pulses or second PWM signal. Will be implemented in future. In the block chart is described the structure of AVD DDS signal generator. You can see the signal paths. Each block part is described in specification. Menu and program stages After generator is switched on the message is displayed in LCD LCD SCREENS Mode. Hz by pressing it in series. Up and Down buttons change the frequency value by step value. After Start button is pressed last settings are saved in EEPROM and signal generation is started. Above functionality is implemented and tested. In a future plans there are few more signal generation modes. By pressing Mode. LCD Screens. 1 Circuit diagram and PCBPCB is single sided with some wiring done in top side. Circuit diagram explanation Microcontroller port pins are connected to R 2. R DAC is connected to D port pins 07 Shift register data line is connected to C ports 0 pin Shift registers synchronize line is connected to port C pin LCD screens E signal is controlled by C ports pin 2 Start button is connected to B port pin 0 Stop button is reset button Up button is connected to port B pin 3 Down button is connected to port B pin 4 Mode. C port pin 3 Mode. C port pin 4 Freq button is connected to C port pin 5 SQ signal is coming from AVR b port pin 2 PWM signal comes out from Port B pin 1. Part list exported from eagle Parts List Tools used. In developing this AVR DDS signal generator There were following tools used Software Hardware tools Few words about firmware. Program is written in C language and can be compiled with Win. AVR2. 00. 60. 42. Programming is done by using AVR ISP and Pony. Prog programming software. Program flow in few words When AVR DDS generator is switched on Initialization of LCD Reading previous settings from EEPROM memory and displaying to LCD Using buttons settings and signals can be changed. When Start button is pressed, new settings are saved to EEPROM and signal generation starts. Note After power up you can press Start to start last saved signal generation immediately Generator is stopped by pressing Stop button which resets the generator. After Reset generator again loads its lasts configuration from EEPROM memory and is ready to start new generation. EEPROM memory stores following data EEPROM data Mode values 0 OUT 1 OUT 2 OUT 3 OUT 4 OUT 5 OUT NOISE 2. PWM OCC 2. 1 PWM SINMDS 2. PWMSQSMDS 2. 3 PWM CMDS Frequency value is divided to 3 EEPROM bytes. Because max theoretical frequency is 1. MHz which hexadecimal value is 0. XF4. 24. 00 Freq2. Freq1. 68Freq70Duty value is from 1 to 9. Program Structure LCD3w. LCD settings. LCD3w. LCD control functionsvoid send. Byte. To. Registeruint. LCDenable. Commandvoid void LCDdisable. Commandvoid void LCDenable. Datavoid void LCDdisable. Datavoid void LCDsend. Charuint. 8t forms data ready to send to 7. HC1. 64void LCDsend. Commanduint. 8t forms data ready to send to 7. HC1. 64void LCDinitvoid void LCDwritebyteuint. LCDdefinecharconst uint. LCDclrvoid void LCDhomevoid void LCDstringuint. LCDGoto. XYuint. LCD are described. EEPROM initialization is done changing parameters are implemented signal generation using in line ASM routines is performed. Testing. For now testing is done by using frequency counter and Oscilloscope. In a frequency range of 1 to 6. Hz works OK. There can be greater frequency range programmed but with less resolution. I think for audio equipment testing there is more than enough frequencies. Discussion. As I mentioned earlier, this is a first trimmed version of AVR controlled generator. It has half of working functionality in many cases this can be enough. Main signals are generated and can be controlled. In a future the functionality can be expanded to add PWM generation using timers. Generator generates signals as they are directly from DAC. There is no variable gain regulation. To be more interesting project there can be VGA amplifier used with feedback to control output signal voltage. The project source code is open to modify and expand functionality. If there will be some good modifications feedback is always welcome. You can download AVR DDS Documentation and AVR DDS Source files as they are. More pictures from the project AVRDDS1 AVRDDS2 AVRDDS3 AVRDDS4 AVRDDS5 AVRDDS6 AVRDDS7 AVRDDS8 Download Eagle project files Some software writing ideas were taken from Jespers Mini DDS. Download Update. Star Update. Star. Download the. Double click the downloaded file. Update. Star is compatible with Windows platforms. Update. Star has been tested to meet all of the technical requirements to be compatible with. Windows 1. 0, 8. 1, Windows 8, Windows 7, Windows Vista, Windows Server 2. Windows. XP, 3. 2 bit and 6. Simply double click the downloaded file to install it. Update. Star Free and Update. Star Premium come with the same installer. Update. Star includes support for many languages such as English, German, French, Italian, Hungarian, Russian and many more. You can choose your language settings from within the program.