GrovePi+ and Scratch


#1

Software (Wheezy), Firmware and Dexter-Software are all updated to the latest versions.
In this article (http://www.dexterindustries.com/grovepi-scratch-software/) it says, you could simply choose the Robot (here GrovePi+) in the new Scratch controller and start programming directly. When I want to do this, Scratch normally starts and also the notification that support for network sensors is enabled appears. The examples are working as well. But let’s say, I would like to just simply turn an LED on and off. I follow the instructions as shown in the previously mentioned article. My LED is not responding… And if I plug some sensors to the GrovePi, they are not recognized by Scratch. So I think I am missing a step and doing something wrong. Do I have to activate a script of some sort? Or do I first have to kind of create variables for these sensors? The article implies that this wouldn’t be necessary. Well, I really hope to get some help, I’d like to try it with my students…

Thanks!


#2

Hello newbie (we were all newbies too. Me not that long ago!)

When you say " The examples are working as well.", are you talking about the GrovePi examples with LEDs (or other sensors) connected to the board?
On that page you linked above, there’s an example with an LED

In the example below, you simply plug the LED in to Port D7, and click on Dex. This will turn the LED on and off.

Did that work? The physical LED turned on and off properly?


#3

Hi CleoQc

Thanks for your answer!

Yeah, the LED is physically working. And yes, I was talking about the example programs provided. They are in the GrovePi Folder on the Desktop. I testet all of them and they are all working. And that makes me think, that I am doing something wrong or that I am leaving a step out when I want to create my own project…


#4

Just making sure, you are indeed running Wheezy, and not Jessie? (Check the Version file on the desktop to see which one).
I’m asking because there’s a known bug (already fixed but just in the last few days) about Scratch on Jessie.

Also, can you take a look in the terminal window, the one that says Do Not Close. Do you see the words “Traceback Error” in it?

Lastly, can you post a screencap of one of the programs you attempted on your own. Something simple and that is not working.

There are no extra steps to do.


#5

It is finally working :slight_smile:

I had to work with variables and loops. I did a very simple thing. Every time, when the air temperature is higher than 29.0 degrees celcius, the buzzer and an LED are going off.

Thanks for your support.


#6

Great! woohoo!

Any idea what the problem was?

And I love your project, although it might get annoying in the deep of summer, depending on where you live :slight_smile:

Cleo


#7

I would first just enter the “code” as shown on the website I linked. For the LED that would be:

When arrow up
broadcast join led join 6 on

But that didn’t work. So I looked at the Scratch eamples again and recognized, that they were working with variables. So I made a variable called status. And when status was 1, the led should start, when status was 0, the led should turn off. And that worked…

So it was really no hardware kind of problem, but simply not understanding scratch well enough.

As for my little project, I was working with loops and replaced the line broadcast join led join 6 on with broadcast join join led 6 on. In the end of the loop, I had to put in a “wait 1 second”; otherwise the programme didn’t work properly.

Well, haha, unfortunately, our summers rarely get as warm as this… :wink:

cheers


#8

Your code should have worked. Watch out for stray spaces. I had this issue often, especially with the join block. It seems to add an extra space at the end. That space will stop the GoPiGo from recognizing the command.

See this little program attached, where port 3 is used