I'm trying to get a sketch going using SoftwareSerial on an R4 Arduino Uno wifi. SoftwareSerial.read() is supposed to read a byte, or -1 if no data is available. The return type of read() is an int, which on this board is an 4-byte quantity, so if no data is available it should return 0xFFFFFFFF. W…

A link to the SoftwareSerial::read() for the Arduino UNO R4 is here . The ringbuffer is a template for any type. SoftwareSerial makes a "char" buffer with it here : ::RingBuffer<char> ringbuf; When a byte is received, it is put as a uint8_t in the buffer here : uint8_t data = 0; ... rx_descr.ringbu…

SoftwareSerial.read() returning value with all the bits set

Projects Networking, Protocols, and Devices

bobcousins January 17, 2024, 11:00am 7

This is a classic legacy C gotcha, char can be signed or unsigned. If you are playing the drinking game, take a shot.

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SoftwareSerial.read() returning value with all the bits set

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