AVR DDS signal generator V2.0

Finally second and improved AVR DDS signal generator is here. First AVR DDS V1.0 generator was only an attempt of running DDS algorithm without any amplitude control. This time I still wanted to keep things simple like minimum count of widely accessible components circuit, single sided PCB that comes together with good functionality. AVR DDS specification AVR DDS signal generator V2.0 is a firmware based DDS signal generator which uses slightly modified Jesper’s DDS algorithm adapted to AVR-GCC C program as in-line ASM. Signal generator has two outputs – one for DDS signal and another for high speed [1..8MHz] square signal – which may be used for reliving microcontrollers with wrong fuse settings or for other purposes as well. High speed (HS) signal is direct output from Atmega16 OC1A(PD5) pin. DDS output is used for all other signals that are generated via R2R resistor network and is adjusted via LM358N …

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