The BinaryBots Totem Crab is available at https://www.binarybots.co.uk/crab.aspx
Here I going to use Edublocks (https://microbit.edublocks.org/) by @all_about_code to control the claw of the Crab to close when button A is pressed (and display a C on the LEDs) and open the claw when button B is pressed. For a discussion on the Crab and what the pins are, etc goto http://robotsandphysicalcomputing.blogspot.com/2018/08/crabby-but-fun.html for more details.
The timing of the opening and closing is controlled by how long the C or O takes to scroll across the LEDs. As an aside, but I found it interesting (it appeals to my geekiness), if you save the blocks, using the Save button; it stores it as an XML file, an example extract is shown below:
Now I want to explore a little the Python editor in Edublocks; to see if it can be used to expand the range of activities. The code as it stands now:
Using some code developed by CBiS Education/ BinaryBots I have added some code to read the Crab's temperature sensor and display "Warm" or "Cold" depending on this. The code uses the struct module to convert between strings of bytes (see https://pymotw.com/2/struct/) and native Python data types. to work with the I2C bus which the Crab sensors use (more details on the bus can be found https://microbit-micropython.readthedocs.io/en/latest/i2c.html ). The code below was then download as a hex file to the microbit as before.
The Crab's reads in the temperature and displays either message "Warm" or "Cold" - currently repeatedly "Warm". The open and closing of the claws still works.
So this was a double win, I had a chance to explore whether the Edublocks Python works as advertised and it does and an opportunity to play with the Crab a bit more; a definite win-win.
Acknowledgement: Thank you to Chris Burgess and the team at Binary Bots/CBiS Education for sending me a copy of the Python code for accessing the sensors on the Crab.
All opinions in this blog are the Author's and should not in any way be seen as reflecting the views of any organisation the Author has any association with. Twitter @scottturneruon