cw_rpi_pico/decoding.txt

30 lines
1.5 KiB
Plaintext

Decoding:
4 wpm to 50 wpm adjustable filter.
Record input, place into ram then process strips of it? Establish WPM and then determine what it says.
Need to establish noise level. Measure for a bit, then set variable as an average. Start measuring when goes above noise level for x samples?
Need to ensure this is added to start of first character so that issues not seen.
to record, need to establish length of signal and an appropriate sample rate. IF input == noise level for longer than x then stop recording.
As adding into ram, could need to strip out 'junk data' so can reduce memory load. Need to ensure a low is kept between high and lows as well as between words.
Can we do something to affect the number of highs?
Does the WPM need to be identified?
If using a constant sample frequency, can try to compare dits to dahs.
Identify HIGH, record number of samples before a noise level is found
Compare to previous HIGH length.
If one longer than the other by x% then dah found.
Pass through recording identifying and then converting samples to dit and dah.
Try to work out pattern for message.
WPM might be required for message establishment? Could be determined through length of 0!!! Hmmmm avoids calculating WPM, increases RAM.
Concern - how quick is this process? Can it cope within 2s? Probably.....
Once words identified, form a message to send to screen. LED changes colour depending on operating mode?
Error handling???? When to reject a series of characters as noise? - might need an option to rebaseline the noise level.