Arduino UNO R3's USB to UART bridge uses for serial communication

[muthukural001]

Hello All,

My friend is having an Arduino UNO R3 board. And, he is saying that USB to UART bridge can only be used for uploading the program and it can not be used for sending/receiving information from/to the microcontroller. I seriously doubt this...I read this "The ATmega16U2 - USB to UART bridge converter holds the microcontroller ATmega328 in reset as soon as Arduino IDE opens...Does it means that closing the IDE will release the microcontroller from reset and we can send/receive information over USB to UART bridge converter...Please suggest...


Thanks,
Muthu

[Ian.M]

Not even that - the IDE has a serial terminal mode that can be used to send & receive serial data to/from the Arduino without closing the IDE, or you can use a third party terminal program.  However the Arduino hardware is designed to reset the AVR when the USB COM port is initially opened, so if you want to keep your firmware running on the Arduino and reconnect to it for serial data without resetting the AVR, you need to do a board mod.