I also want to use up to 3 of the I2C seeeduino grove motor driver V1.1 shields and could at least get 2 to work,
but I still have problems with right adressing for independant motor control of more than one shield connected.
These modules use the I2C-bus as a joint connection.
The base grove shield provides 2 places to connect these modules, named IIC, the rest of the connectors are used with analog or digital pins only.
One connector is right next to the reset button- side connection and one is a top connector - both with
print label aside.
As far as I understand the documentation, you need the I2C bus-connection only, I tried it with the 2 connectors mentioned.
I assume, that in order to use 3 of them, I simply can connect them in parallel, which the IIC-bus supports.
Hope, this is a meaningful information to you.
I am looking for full documentation on the shield control functions and how they work alltogether.
The code sample works o.k. with a single shield, if you change the wire.send() to wire.write() …
Hope this hint can help you.