Add SRAM upload maximums

[pfeerick]

Added upload.maximum_data_size config entries to all Digisprk board types so that the Arduino IDE can calculate percentage of SRAM usage and warn if too much SRAM is used in a sketch.

Further details as to how I determined the upload maximum to be 496 bytes, and how this affects the end user can be found in this forum post.

In a nutshell though, it goes from simply reporting ...

... to giving a overview of how much memory is free ...

... to being able to bug out when the user isn't aware of how strings gobble up memory ;)

[per1234]

Closes #44

[ArminJo]

This pull request is included in the new version 1.6.8 of Digistump avr core.

[ArminJo]

Please could you be so kind and close the issue, since this repo is abandoned.
Thank you!
Armin

[pfeerick]

Have you tried emailing Erik to to see if he will archive this repo, rather than asking everyone with open PRs to close them?

[ArminJo]

I am not aware of al the consequences of an archived repo.
As long as this is the official linked repo for Digistump, I thought it is good to have the possibility to create new issues.
Or archiving and place a link to the successor repo, but I do not assume that Erik will do this.

[per1234]

I don't see what the problem is with having open PRs. Even if they aren't going to be merged, they can be helpful to the people who use this project and run into these problems. I don't think they should be closed unless they are actually invalid.

@ArminJo are you authorized to speak on behalf of Digistump in these matters?

[ArminJo]

@per1234
I was a "victim" of all this dead and old code, so I decided to help me and others by creating a fresh version of the Digistump software.

[per1234]

I decided to help me and others by creating a fresh version of the Digistump software.

Thank you for that. From what I see providing support on the Arduino forum, digispark boards (and their clones) seem to be very common, so it's great if there is an actively maintained platform for them.

However, I still don't see a benefit to closing the PRs in this repo. Instead, what you could do is add links to these PRs when you cherry pick the commits into your fork, which will add a reference in the PR thread here that people can follow to find your fork.

[ArminJo]

I request only this PR's to close, which I included in the new version, since they are now obsolete.
Do you think it would be better to leave them open, in order to see the link to the new repo?
I never considered it to do it this way.

[pfeerick]

I see per1234 is thinking what I was thinking when I wrote that comment earlier. If the issues still exist in this repo, the PR is still valid for this repo. If you want to say that you've fixed it in your repo, and link to that, you're entirely welcome to. But until this repo is officially abandoned or archived, can't say I agree with closing PRs to issues it still has. That is not to say I wouldn't recommend others to use your repo instead of this one! ;)

[ArminJo]

@pfeerick @per1234 You are totally right!
Do you think, we have a chance to reach Erik, to ask him to archive this repo adding a link to the new one, or to let us maintain it with a appropriate disclaimer?

[pfeerick]

I'll send him an email now. I have been in communication with him in the past, and am also a backer of a current project, so there is a good chance at least of a reply! ;)