Flipper always initially transmits a "1" an ignores sequential values of same logic level

top signal is what the flipper should send, bottom what it actually sends
the signal starts with a long 1, which is noch included in my sub file. additionally it ignores ‘pauses’ that i’ve added in between the repetitions. e.g. -2100 -15000 results in just -2100 and initial pauses with negative values are also ignored and it will always send a 1 for some ms

the flipper transmits only what you said, the only limitation is, the intervals must alternate, low is high, the transfer starts from high (if not, the flipper will create it itself) everything

ok, alternating states make sense, but the main problem is the beginning. even if i start with a 1, the flipper adds a longer 1, followed by a short 0 right before my signal

here’s my signal once;

Version: 1
Frequency: 433920000
Preset: FuriHalSubGhzPresetOok270Async
Protocol: RAW
RAW_Data: 300 -2100 300 -2100 2100 -300 2100 -300 300 -2100 300 -2100 2100 -300 2100 -300 300 -2100 300 -2100 2100 -300 2100 -300 300 -2100 300 -2100 2100 -300 300 -2100 2100 -300 300 -2100

I recorded your sub with another flipper:

Filetype: Flipper SubGhz RAW File
Version: 1
Frequency: 433920000
Preset: FuriHalSubGhzPresetOok650Async
Protocol: RAW
RAW_Data: 630115 -1150 277 -2088 317 -2082 2089 -316 2091 -324 281 -2112 301 -2100 2093 -296 2133 -298 275 -2108 305 -2102 2089 -292 2081 -330 275 -2112 303 -2106 2117 -298 277 -2114 2125 -298 275 -113938 131 -200 65 -168 65 -300 65 -132 783 -260 163 -264 165 -100 65 -132 131 -13490 65 -430 831 -332 199 -132 97 -232 99 -634 97 -166 231

I think this is the behavoir you meant. I dont know why this happens, maybe the chip starts with 1, maybe sourrounding noise.

It might be a good idea to start your RAW_Data with a long 0 to make sure the signal is recognized correctly.

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yep, my ugly solution is 1 -15000 300 -2100...
but this also transmits a 1 much longer than 1 us

no need to look at what exactly the transfer starts from, (1us flipper will definitely not transfer, as cc1101 will not be able to do this). there is a lot of noise on the air and that you start with 1us even with 1000 does not matter. the main thing further is your correct signal. and it is not enough to transmit it 1 time, you need to repeat it 4+ times so that the receiver hears it, super tune in and adjust it. here already in repetitions without this starting signal, only useful

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what’s wrong? conveys exactly what you wrote. start CC1101 need to initialize the transmission. at the end you transmitted a low level and CC1101 worked it out, then a shutdown occurs (without changing the level) … repeat your message several times and everything will fall into place. on the air all the time with the transmission of 1 packet WITHOUT a preamble, nothing will work

300 -10000 worked for me as preamble on my garage door opener. No need for repeating.

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