44
votes
Mac OSX Yosemite no serial ports showing for Uno R3
Probably, you have Chinese Uno analog which works on CH340 USB-to-serial chip, so you need to install driver for it.
Steps to fix:
Install the CH340 driver
Run the command in Terminal: sudo nvram ...
- 541
39
votes
First time set up- permission denied to usb port- ubuntu 14.04
From the documentation:
Open Terminal and type:
ls -l /dev/ttyACM*
you will get something like:
crw-rw---- 1 root dialout 188, 0 5 apr 23.01 ttyACM0
The "0" at the end of ACM might be ...
- 17.6k
18
votes
Accepted
Can the Arduino interface with USB devices without the USB host shield?
First things first you need to learn the basics of how USB works.
In USB there are two main "things": Hosts and Devices.
You have one Host (usually your computer) and many Devices (such as Arduinos, ...
- 104k
15
votes
Mac OSX Yosemite no serial ports showing for Uno R3
The cable that shipped with my Arduino Uno worked for power but not data transmission so the /dev/tty.usbmodem was not showing up in the Tools --> Port menu. After I switched to a different cable, the ...
- 151
15
votes
If the USB gives 5v, how can the Arduino supply 5v to the 5v pin? (And another question)
Actually, Arduino is powered at 5V (the 5V pin and the ATmega328p are connected to the +5V rail in the board). The point here is where do those 5V come from. Basically, from 2 possible sources:
USB. ...
- 2,103
10
votes
Accepted
Difference between /dev/ttyACM0 and /dev/ttyS0 (Arduino IDE ports under Linux)
/dev/ttyACM0 is a USB communication device (CDC) of sub-type "abstract control model" (ACM). That is what the Arduino is.
/dev/ttyS0 is a hardware serial port - the (typically) 9-pin D connector on ...
- 104k
8
votes
Arduino Nano not visible in Serial Ports (Mac OS)
Is it an original Nano or a clone?
The original Nano uses FTDI's FT232 ship, whereas clones use the CG340 USB-to-TTL chip. The former works fine straight away Mac OS Sierra, whereas the latter needs ...
- 2,103
8
votes
Accepted
CH340 max serial speed
CHG340 supports common baud rates: 50, 75, 100, 110, 134.5, 150, 300, 600, 900, 1200, 1800, 2400, 3600, 4800, 9600, 14400, 19200, 28800, 33600, 38400, 56000, 57600, 76800, 115200, 128000, 153600, ...
- 1,336
7
votes
Accepted
Is it OK to Serial.print(message), when the USB cable is not connected to a host PC?
It is OK to write out serial data with nothing connected.
In case (2) "Arduino + USB interface chip", the arduino has no idea if anything is connected or listening to the serial port. The ...
- 4,361
7
votes
Accepted
External 5V Power and USB Serial
Having used counterless Arduinos and clones, I can tell you that you can connect both without worrying about any danger. Unless you have a very faulty board, your pc won't be damaged, almost surely ...
- 303
6
votes
Powering an Arduino Mega with external USB Power Bank?
I have a "USB power bank" with two USB ports, which I use to power some projects.
I have discovered that my bank (i.e. your mileage may vary!) shuts off unless my project draws at least 50mA. If your ...
- 2,373
6
votes
Mac OSX Yosemite no serial ports showing for Uno R3
This fixed the problem for me:
http://blog.sengotta.net/signed-mac-os-driver-for-winchiphead-ch340-serial-bridge/
... and the direct link to download.
EDIT: I have one of the cheap clones with a ...
- 169
6
votes
First time set up- permission denied to usb port- ubuntu 14.04
All you need to do is add yourself to the dialout group as described in the answer by Ignacio Vazquez-Abrams. This is done in the terminal by typing:
sudo usermod -a -G dialout $USER
You do not need ...
6
votes
My Digispark board won't show up in Ports tab in Arduino IDE (OSX)
I don't think it is supposed to. The Digispark briefly connects in "bootloader" mode, which you spotted as "Vendor-Specific Device:".
Then after 5 seconds it runs the loaded sketch. If your sketch ...
- 36k
6
votes
Arduino Leonardo as keyboard for an iPad
If indeed the descriptor is the problem then yes you can change it.
In the core file USBCore.h is the line:
#define D_CONFIG(_totalLength,_interfaces) \
{ 9, 2, _totalLength,_interfaces, 1, 0, ...
- 104k
6
votes
Accepted
How can I detect which baudrate a virtual COM port is set to?
From looking at the source it appears that on 32u4 based boards Serial includes extra methods to access the settings from the USB host:
see: https://github.com/arduino/ArduinoCore-avr/blob/...
- 2,110
5
votes
Mac OSX Yosemite no serial ports showing for Uno R3
Yosemite 10.9 (and OS X 10.10 and newer) requires a signed USB driver kext (kernel extension). You can find one on the FTDI web site here: http://www.ftdichip.com/Drivers/VCP.htm
Use version 2.3 for ...
- 279
5
votes
Mac OSX Yosemite no serial ports showing for Uno R3
This site fixed the problem for me:
http://kiguino.moos.io/2014/12/31/how-to-use-arduino-nano-mini-pro-with-CH340G-on-mac-osx-yosemite.html
...somebody else has made an alternative to the ftdi ...
- 59
5
votes
Keyboard.print() skips keys
The Arduino assumes a US keyboard layout. The thing with keyboards is they don't actually send the letters or symbols that are printed on the keys. Instead the send a scan code that defines where on ...
- 104k
5
votes
Accepted
Pinout for Leonardo USB
The USB does not go to pins 0 and 1. The UART goes to pins 0 and 1 - that is a totally different interface.
The USB is connected to dedicated USB pins on the chip. If you look at the Leonardo ...
- 104k
5
votes
Protecting your computer from stupid (arduino) mistakes
Both the arduino and a USB port do have some protection against wrong connections and such. The arduino has a diode to prevent wrong polarity to reach your power supply, it also have a resetable fuse (...
- 466
5
votes
Why is there already text in the serial monitor before the Arduino initializes?
It's because the Arduino has started running the sketch and placed data into the USB chip's buffer. You then open the serial monitor which then opens the serial port thus resetting the Arduino. So the ...
- 104k
5
votes
Accepted
Which Arduinos have a true serial port?
There seems to be quite a few Arduinos without a 32U4, like:
Uno (you mentioned it already)
Mega (same)
Lilypad Snap
MKR1000
Pro
Pro Mini
Zero
Due
Ethernet
Mini
Nano
MKR Zero
See the list at ...
- 12.8k
5
votes
How to convert USB to PS/2?
Many USB keyboards (certainly older ones, though almost certainly not wireless ones) are also PS/2 keyboards. The wiring of the cable is all that differs, and the chip in the keyboard changes its ...
- 104k
4
votes
Accepted
Regarding the USB port, what is the difference between Uno/Mega and the older boards?
The older Arduino boards used an FTDI FT232R chip to handle the USB port. This chip is a special purpose, USB to serial UART interface.
In the current Arduino boards, the USB to serial conversion is ...
- 146
4
votes
Mac OSX Yosemite no serial ports showing for Uno R3
This exact same thing happen to me on my mac running the same operating system. I had to restart this system a few times to get it to work. I restarted it with the arduino plugged in; and that worked ...
- 45
4
votes
Can the Arduino interface with USB devices without the USB host shield?
No. USB strictly distinguishes between host and device roles. A few chips have functional blocks capable of performing either role, but the 8u2/16u2 are not examples of this.
Typical USB serial ...
- 5,348
4
votes
100khz square wave with 50% duty cycle
The problem with your program is that it does not loop fast enough. Each
call to delayMicroseconds() should take roughly the requested time to
execute, but the CPU also needs time to execute the rest ...
- 39.6k
4
votes
Accepted
How to send Serial.Print only If Serial Connection is open?
The Arduino Mega's "serial" connection comes from an external chip implementing USB-serial conversion. While this chip knows if a session is open with a host, the standard design has no way to share ...
- 5,348
4
votes
Using ATTiny85 as a USB HID Mouse
Due to the lack of USB-Support of the ATtiny85 you will be forced to use something like V-USB as the tutorial does. This might have implications when you are targeting a commercial product.
...
- 1,503
Only top scored, non community-wiki answers of a minimum length are eligible