First time use

Preparation

Automatic installation of arduino-cli is not yet implemented. In the interim you need to do this manually.

You must also provide the path to arduino-cli.exe in extension settings (see manual installation instructions).

When you open an arduino project that you have not previously opened with this extension, VS Code will look like the following illustration. Look at the right hand end of the status bar.

• M:undefined means you have yet to set a serial monitor port.
• Choose a board means what it says.

Click on Choose a board to make QuickPick list appear:

Type the name of your board. VS Code will do fancy progressive matching until you find and click your board.

I have a Nano:

Notice that the vanilla Nano says it uses arduino:avr whereas other flavours say they will install other cores. This is because I have already installed the arduino:avr core. If you select a board that requires a core that isn't installed the extension will install it.

Now that the extension knows what board you have it will prompt you to pick a serial port. Currently this fails to populate the list. Click on M:undefined and it will retry successfully. If you click on D:NOT SET you will get a list of deployment methods which includes all the hardware programmers supported by your board and all the detected USB serial ports.

When you open the INO file, Compile and Deploy commands should appear at top right, like this:

The Flash command will not appear until you specify a hardware programmer because you can't flash the bootloader without one. Notice that I have already selected the USBasp programmer in this snap.

Now check that everything works

Compile

With the extension installed and an INO file open, click Compile. When the dust settles, you should see something similar to this.

In the OUTPUT pane compilation results are displayed. In settings you can request verbose compiler output.

Deploy

Deploy compiles before it deploys. You don't need to compile first.

With the extension installed and an INO file open, click Deploy.

As with Compile, results are displayed in the OUTPUT pane. Deploy results are always verbose because in addition to providing better feedback in a potentially slow operation, it allows the extension to detect failure/retry and abort instead of silently trying a sixty second operation ten times.

Here is a sample successful deployment using a USBasp programmer.

Sketch uses 9452 bytes (30%) of program storage space. Maximum is 30720 bytes.
Global variables use 884 bytes (43%) of dynamic memory, leaving 1164 bytes for local variables. Maximum is 2048 bytes.
"C:\Users\Peter\AppData\Local\Arduino15\packages\arduino\tools\avrdude\6.3.0-arduino17/bin/avrdude" "-CC:\Users\Peter\AppData\Local\Arduino15\packages\arduino\tools\avrdude\6.3.0-arduino17/etc/avrdude.conf" -v -V -patmega328p -cusbasp -Pusb "-Uflash:w:d:\Arduino\ArduinoPumpController\build\arduino.avr.nano/ArduinoPumpController.ino.hex:i"

avrdude: Version 6.3-20190619
         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "C:\Users\Peter\AppData\Local\Arduino15\packages\arduino\tools\avrdude\6.3.0-arduino17/etc/avrdude.conf"

         Using Port                    : usb
         Using Programmer              : usbasp
         AVR Part                      : ATmega328P
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
           flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
           lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
           signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

         Programmer Type : usbasp
         Description     : USBasp, http://www.fischl.de/usbasp/

avrdude: auto set sck period (because given equals null)
avrdude: warning: cannot set sck period. please check for usbasp firmware update.
avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: auto set sck period (because given equals null)
avrdude: warning: cannot set sck period. please check for usbasp firmware update.
avrdude: reading input file "d:\Arduino\ArduinoPumpController\build\arduino.avr.nano/ArduinoPumpController.ino.hex"
avrdude: writing flash (9452 bytes):

Writing | ################################################## | 100% 6.16s

avrdude: 9452 bytes of flash written

avrdude done.  Thank you.