I have popular CH340 USB relay module, like this one. To turn it on/off I have to type in Linux bash:
echo -en "xA0x01x01xA2" > /dev/ttyUSB0 ; turns relay on
echo -en "xA0x01x00xA1" > /dev/ttyUSB0 ; turns relay off
But how to know relay’s CURRENT STATE without switching it? Is it possible?
I tried to find CH340/CH341A chip documentation, but without success.
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