Variability in waveform timing of coupled remote_transmitter routines

ESPHome
1

I am seeking to emulate a Wen 3417 remote control with 3 buttons (OFF, ON, TIME)
I reverse engineered the encoding which consists of the following:

  • Pulse length is ~320ms

  • Sync sequence - 25 alternating high/low pulses of length 320ms per high and per low element

  • Pause of length ~ 9600ms (30 pulse units)

  • Message consisting of 16 bits where: ones consist of 3 Hi followed by 1 Low while zeros consist of 1 Hi followed by 3 Low (total length = 4 pulse units = 4* 320 = 1280ms)

  • Message is repeated 3 times with 9600 ms between them (30 pulse units).

I got it to work by using remote_transmitter.transmit_rc_switch_raw twice separated by a delay. The first call creates the sync sequence and the second creates the 16-bit messages.

Code is like:

  - platform: template
    name: "Dust Collector OFF"
    on_press:
      # Sync Signal
      - remote_transmitter.transmit_rc_switch_raw:
          code: '1111111111111111111111111' #25 hi/low pulses
          protocol:
            pulse_length: ${pulse_length_us}
            one: [1, 1]  # Alternating high/low for sync
            sync: [0, 0] # Don't precede with sync
      - delay: ${post_sync_pause}  # Pause delay after sync

      # Message
      - remote_transmitter.transmit_rc_switch_raw:
          code: '1100001110010001'  # OFF signal (16-bytes)
          protocol:
            pulse_length: ${pulse_length_us}
            zero: [1, 3]   # 1 high, 3 low for a '0' (default)
            one: [3, 1]    # 3 high, 1 low for a '1' (default)
            sync: [0, 0]

          repeat:
            times: 3
            wait_time: ${pause_length}

where pause_length=9600ms and pulse_length_us = 320

However, whatever value I use for post_sync_pause to set the delay between sync and message, the actual silent time varies significantly – ALTHOUGH THE REMOTE PROGRAM STILL WORKS.

I imagine the problem is due to the fact that the code outside each single remote_transmitter.transmit_rc_switch_raw routine is non-blocking with delay variations caused by things like Wifi interrupts (I am using a D1-Mini version of an esp2866)

  • Is there any way to make this code section blocking so that the end-to-end timing is repeatable?

I imagine I could use a lambda expression to combine the sync/delay/message all into one raw code but that would be messy…

  • Any other solutions?

Or is the ‘pause’ time between sync and message generally insensitive for these types of coding schemes so I should just leave it as-is and accept the variability.

  • Am I diagnosing this and understanding this correctly?