Serial Data Transmission with RF - Improvements

The "pipe-lining" fix in the transmitter was still bugging me.

Fortunately I came up with a solution. With the CPU clock slowed down to 62.5kHz, half what I had been required to use, and NOP instructions in both _TXOn and _TXOff, I achieved the jitter free waveform I was after.

I assume that with enough NOP instructions the pipeline was being forced to reload more often and the jitter caused by random reloading was gone. 

In my first application, a shed door monitor, I expect a single D cell will last over 4 years. The maths suggest 11 years but can an alkaline battery last that long without leaking and self discharge reducing the life?

Briefly,

: _TXon  [ 1 PC_ODR _TxEn ]B!  ;
: _TXoff  [ 0 PC_ODR _TxEn ]B! NOP NOP NOP NOP NOP NOP ; \ 8 bytes 

was changed to

: _TXon  [ 1 PC_ODR _TxEn ]B! NOP NOP NOP NOP ;
: _TXoff  [ 0 PC_ODR _TxEn ]B! NOP NOP NOP NOP ; 

I then used the ]M! command to build up the assembly bytes for a complete On and Off packet without any calls.