You can see a scope output attached. The problem is consistent, but i don't know why it happens. Other factors: the problem does not occur when the software serial pin is disconnected (code not changed) the problem persists when the sw serial is not polled, but the wire is connected The module …

When software serial RX is active, bytes are dropped on hardware serial RX

Robin2 October 20, 2019, 2:05pm 10

kolompos:
So... let's call it SOLVED ? Although the mystery isn't solved.

The standard SoftwareSerial library is not great.

...R

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