Amateur Radio FSK/CW interface Arduino sketch for nano board
An FSK / CW interface based on the Arduino nano.
FSK Specifications: 5 bit Baudot baud rates 45.45, 50, 75 and 100
CW Specifications: 5 to 100 WPM dash/dot ratio adjustable 2.5 to 3.5 in-line increment decrement WPM using ^ and | characters incremental size user adjustable
Both: an internal buffer of 300 characters is available for buffered transmit. PTT signal generated by Arduino
Hardware requirements: Arduino nano or compatible (author used nano from Elegoo) LTV-847 quad opto-isolator 4 620 ohm ¼ watt resistor (should work with 500 < R < 820 ohm) suitable connectors to interface to transceiver
Default pin assignements for nanoIO circuit design: D9 / PIN 9 - spare D10 / PIN 10 - PTT D11 / PIN 11 - FSK_PIN D12 / PIN 12 - CW D5 - Left paddle in D2 - Right paddle in
This sketch can be configured to be pin compatible with MORTTY, a do-it-yourself kit produced by N8AR and K8UT. MORTTY is an inexpensive minimalist solution that depends upon the configuration and control features incorporated in the computer program. It has only two inputs and two outputs: a USB serial port interface to the computer, a CW paddle, a PTT signal line, and a shared CW/FSK signalling line.