legacy.py rewritten to use new device class interface

LegacyDevice tx path commissioned end to end

Renamed encoder as TwoBit, as it encodes two bits per byte. ...

This is the encoding protocol used with legacy OOK devices

factored out python2/3 differences on raw_input

Renamed new radio2 module as radio, and removed old code

Restructured switch.py so we have a tx-only test. ...

This is in preparation for pushing the FSK transmitter into radio.c

Refactored so that we can create a tx-only switch loop tester. ...

This will be useful for integrating a new FSK transmitter without receiver

Legacy test passed

Tested with a house address captured from an Energenie hand controller. ...

Captured the bit pattern on GnuRadio and hand decoded.
Address was 0xA0170
Programmed this into legacy.py, and plugs previously learned
to the hand controller switched correctly

Tested with different house codes, works fine

Improved configurability of message repeat patterns. ...

Tested with different repeat lengths.
Optimum seems to be 8 inner, 1 outer transmits

Tested with learning mode. ...

Works with all 4 switch patterns.
Can now independently switch 4 switches.
Some occasional RF reliability problems that need measuring.

Set repeats to get maximum OOK payload burst of 400mS

encoder now adds preamble. ...

lecacy.py now uses new C radio driver

Tiny tidy up

Baud rate for OOK increased to 4800bps to bring in line with latest Energenie builds. ...

Sync pattern now recognised correctly as 0x80,0x00,0x00,0x00
Switching is eratic, but learning always learns.

Regular schedule for switch1 transmit test

Added feature to test a single switch repeatedly

Started refactoring

Pre-factoring work done prior to pushing more code into the C domain.

Tweaked payload format further. ...

Reset all devices and re-learnt the house code
Can now switch all devices on and off, together, and independently.
legacy.py test code now demonstrates this in a loop

Added a test mode to test all 16 patterns of legacy control messages. ...

Run legacy.py and try numbers 0 to F in learning mode.
In theory you should be able to select 4 different switch addresses
plus an 'all addresses', but I can't get this to work on my 7 plugs,
they all respond as switch number 1 regardless of what code I send
in learning mode.

Attempts to get multiple device addresses working. ...

Seems to be a discrepancy between documentation and sample C code.
Stopping here until I get this clarified.

Fixed legacy import errors

Renamed modulator as encoder

7 legacy adaptors now turning on and off with this trimmed code

Got old code working again. ...

Looks like the extra bytes inserted by the buffer bug actually make it work.
This is probably related to sync bytes

Tweaks to legacy learn feature

Rewrote legacy.py to use new modulation code. ...

Not yet tested on a real Raspberry Pi

Slight improvements to timing of message transmission. ...

Still seem to get 'failed to send repeated payload to HRF' after a while
Suspect the FIFO is filling up or something.