Arduino Digispark support

[silvioprog]

It would be nice to add Arduino Digispark support (ATtiny85-based board).

When we try to upload the firmware (just a blink example), it raises the following error:

Error: No ports selected. Please select a port.

however, when we try to configure the port, it shows only NO PORTS DISCOVERED, as following:

[ubidefeo]

@per1234 I saw you marked it as a bug, why so?
It could be that the driver installation didn't go through and I also saw in their troubleshooting and wiki that once the board is configured as a USB device it will only be visible for 5 seconds before it starts acting as a peripheral.
Might that be one of the issues?

[per1234]

why so?

In the case of DigiSpark is a vUSB device, The micronucleus uploader doesn't use serial.port, so Arduino Pro IDE's requirement of having a serial port selected is unnecessary.

This requirement means the only way to upload to a pure USB device is to select some random serial port, even though it won't be used for the upload. Some people might not even have a serial port available for this purpose.

A workaround the platform author to get around this limitation might be to not define the upload.protocol property, so the "always Upload Using Programmer" behavior is used (which doesn't require a serial port), but then you might have issues of the user needing to have the correct Tools > Programmer selection. Anyway, Pro IDE also doesn't support the "always Upload Using Programmer" behavior currently (https://github.com/arduino/arduino-pro-ide/issues/309).

The Arduino IDE can handle this sort of use case fine, so it's certainly achievable.

[ubidefeo]

@per1234
We need to make sure this use case is covered, we'll potentially have it with other HID or DFU based boards.
I'll put it in our task-list, thank you for chiming in 👍

[ubidefeo]

@per1234 I have been researching this case.
I don't have this board, but tried to upload using the Java IDE anyway to see the command and any possible error.
I get an error I cannot recognise
Error while uploading: missing 'program.params.verbose' configuration parameter

from the CLI, running arduino-cli compile -b digistump:avr:digispark-tiny -u -P micronucleusprog I also go nowhere and get
Error during Upload: programming error: recipe not found 'program.pattern'

Maybe there's something wrong with the upload recipe in the platform definition?

[per1234]

I don't have this board

Same here.

I get an error I cannot recognise
Error while uploading: missing 'program.params.verbose' configuration parameter

This is because the platform is not designed for use with "Upload Using Programmer". I don't know why they added that "micronucleus" programmer because it can't be used.

You need to do a standard "Upload":
http://digistump.com/wiki/digispark/tutorials/connecting#using_the_digispark_with_the_arduino_ide:~:text=You%20do%20not%20need%20to%20plug%20in%20your%20Digispark%20before%20invoking%20upload

Hit the upload button. The bottom status box will now ask you to plug in your Digispark - at this point you need to plug it in - or unplug and replug it.

You'll see the upload progress and then it will immediately run your code on the Digispark.

from the CLI, running arduino-cli compile -b digistump:avr:digispark-tiny -u -P micronucleusprog I also go nowhere and get
Error during Upload: programming error: recipe not found 'program.pattern'

Remove the -P micronucleusprog from the command.

Maybe there's something wrong with the upload recipe in the platform definition?

upload is fine. It's the missing definition for the program action. In the time the Digispark boards platform was written, you had access to all programmers of all platforms and the platform.txt of the boards platform of the selected programmer was used rather than the digispark platform.txt, so it would get the program action definition from the programmer's platform. That behavior was changed in Arduino IDE 1.8.13 and now each platform must provide definitions for all supported programmers.

[ubidefeo]

@per1234
got it. it works with CLI (as in "it's waiting for me to plug").
so... we need to relax the port selection policy.
we'll get to it in the next sprint or two, should be doable without much hassle

[kittaakos]

For the record; to properly support this use-case in the new IDE, we have to remove all premature checks on the IDE side before giving back the control to the CLI to verify/upload. This means we cannot warn the user if a board is not selected and the user verifies. We also cannot notify the user if she wants to upload and no board/port is picked.

Current state:

1. Verify/Upload without a selected board:
   

2. Upload without a selected port:
   

[kittaakos]

Proposed changes:

1. Verify without a board selected:
   

2. Verify with a selected board but without the corresponding core installed:
   

As one can see 👆, we cannot distinguish between the "no board was selected" and "the core is not installed for the selected board" cases. Both results in a no FQBN was set error.

3. Uploading to a board that is not connected (no port was set):
   

4. Upload using a programmer when no programmer is selected:
   
   

This is tricky, when no programmer is selected, the upload using programmer will trigger an upload. There is no dedicated gRPC API for upload using programmer, this means, if the user does not set a programmer but performs upload using programmer, it will result in a common upload call on the CLI.
(CC: @ubidefeo)

5. Burn bootloader without a programmer set:
   
   

[kittaakos]

This is tricky, when no programmer is selected, the upload using programmer will trigger an upload. There is no dedicated gRPC API for upload using programmer, this means, if the user does not set a programmer but performs upload using programmer, it will result in a common upload call on the CLI.
(CC: @ubidefeo)

I did another iteration with arduino/arduino-cli#1045 and it works as expected:

• I have selected my Zero board,
• the core was installed,
• the FQBN was set,
• serial port was set,
• programmer was not set

I see the expected error, instead of the silent upload.