Scratch, Raspberry Pi and RC-Car

Now that I have a Rspberry Pi driving an RC car via an HTML interface, my thoughts turned to wondering if I could use Scratch to drive the car.

First thoughts are how do I get scratch to interface to my GPIO pins to drive the car, and secondly whether scratch is on the tablet to do the control, or on the Raspberry Pi wih a programming interface on the tablet.

Possible links to investigate:
https://www.raspberrypi.org/blog/scratch-2-raspberry-pi/       Looks good.

https://www.raspberrypi.org/documentation/usage/scratch/     Basic, but leads to previous

It might be easier than I think.

https://www.raspberrypi.org/blog/scratch-3-desktop-for-raspbian-on-raspberry-pi/
And we are up to scratch 3 in 2019

This last suggests a simple electronics extension that could be useful.

Memory Cards, Applications and RC-Cars

This is doing my head in, so I have to get it down. I almost need a multidimensional spreadsheet.
My memory cards are numbered. The RC-car apps that I have developed are numbered, and the Cars themselves are numbered.

I did do some tests to see which cars would work with a PWM speed control, but I can't find the record of that experiment.

So CArd 4 is now in RC-Car 3
And Card 7 is in RC-car 2. Card 10 is a duplicate of card 7

Card 4:
App-py-7        PWM control of motor
                        Steering is  2 pin on/off control

App-Py-8       steering is PWM-servo
                       Motors driven by 2-pin on/off control

App-Py-PWM-Test          Motor control calculating PWM duty cycle
                       no steering

App-py.old   -> backup of py-7

CArd 7:
App-py  2-pin on/off control for both motors      Dated 2018-10-31 - An early one.
              using GPIO 18/23  and 10/11

Card 3:
App-py  2-pin on/off control for both motors      Dated 2018-10-31 - An early one.
              using GPIO 18/23  and 10/11
              with double push on forward to stop. (31-1-2019)