USB Morse Keyer

USB Morse Keyer is a microcontroller-based auto keyer project with following features:

USB / straight key / iambic key inputs.
Support for both standalone and USB operating modes.
64-character USB typeahead buffer and 6-character Morse key typeahead buffer.
Support 5, 10, 15 WPM.
6-page message memory.
1W Audio output.
Audio and PTT output interfaces.
32 character display

Final view of the USB auto keyer.

The USB interface of this unit is designed to work with most of the operating systems. It emulates a virtual serial terminal to transfer keystrokes to the keyer. In most of the operating systems, this interface works without installing any additional device drivers. To submit keystrokes user can use any serial terminal software such as PuTTY, Hyper Terminal, Minicom, etc.

This keyer is designed to work with 7V to 16V DC input voltage. The most recommended working voltage is 9V.

The bottom side of the USB auto keyer.

To reduce the dimension of the PCB this unit is designed with combining both through-hole and surface mount components. To facilitate future upgrades and modifications, the PIC16F886 MCU sticks with the standard 28-pin DIP package.

This is an open-source hardware project. All the design files and firmware source code are available at the project repository at github.com. The project documentation with all the details which including assembly details, firmware uploading, compilation, and usage instructions are available at the project repository's wiki.

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