Timeline for Arduino Uno RX/TX pins
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Aug 1, 2013 at 18:36 | comment | added | Anindo Ghosh | @wollud1969 Like I mentioned, Your code can always reset TXEN. The code for both controllers is open source. | |
| Aug 1, 2013 at 14:03 | comment | added | wollud1969 | I was talking about the TXEN flag on the communication controller, not the main controller. My code has no influence on the communication controller (so, I could not disable this flag) but the communication controller knows when USB is plugged or unplugged, so - to my understanding - it could disable TXEN when USB is unplugged and the send buffer is empty and could reenable it when USB is plugged again. | |
| Aug 1, 2013 at 12:02 | comment | added | Anindo Ghosh | @wollud1969 Your code can always reset TXEN. However, the reason USB transmission is left enabled is because USB can be plugged in or disconnected at any time, without resetting the board, so long as power is supplied to the board separately. | |
| Aug 1, 2013 at 7:24 | comment | added | wollud1969 | Okay, I found the code. Indeed, TXEN is set somewhere in the init phase and never reset. So, indeed, TX is always active. Ugh! Maybe I should ask in an Arduino forum, why it is not reset to disable TX when no USB is connected. However, for now, I need to overwrite the signal behind the resistor with enough current and have to remove my shield when firmware is uploaded to the Arduino main controller. | |
| Jul 31, 2013 at 19:02 | comment | added | Passerby | @wollud1969 github.com/arduino/Arduino/blob/master/hardware/arduino/… | |
| Jul 31, 2013 at 17:19 | comment | added | wollud1969 | BTW: has anyone a hint for me where on the arduino homepage or in the arduino repo I could find the code for the communication controller? | |
| Jul 31, 2013 at 17:18 | comment | added | wollud1969 | Okay, but I haven't found any statement about how the communication controller drives the line. I really want to avoid SoftwareSerial. It might to be a last resort howvever. | |
| Jul 31, 2013 at 13:22 | history | answered | Anindo Ghosh | CC BY-SA 3.0 |