BitXUltra firmware for the BITX40 by VK6MN

This document covers the firmware written for the BITX Raduino board 
with the BITX40 transceiver as supplied by www.hfsigs.com. 

The firmware started out as the original Bitx firmware by Ashhar Farhan, 
VU2ESE (although not much of that is left here) and has grown to incorporate 
ideas from the uBitx and other Bitx related material on the internet, 
including several blog posts by Don Cantrell, ND6T.  

All the code in version 1.0 that was not part of Ashhar's original firmware 
is written from scratch by Mike, VK6MN.

This firmware uses an 'everything in' approach, with #defines used to enable 
the various options. As a result it can be built to make your radio as 
advanced or as streamlined (simple) as you like without having to maintain 
more than one version. 
The simplest version is the same as the original BITX40 firmware and only 
provides control of the DDS frequency, with a calibration button.
The most complete version provides shuttle tuning, PTT control, a menu, RIT, 
USB/LSB, CW with Straight Key, Paddle or Bug, setting the sidetone frequency, 
saving the current state as default, a channel mode with up to 40 channels, 
up to 6 VFOs, an SWR/S-Meter, CW Beacon, Antenna Analyser and more! 
(and it's possible to make it all fit at the same time!)

See BitXUltra.odt (Open Document Text) for full details on the features
available, how to enable them and the BITX hardware connections needed 
to use them.