Page 1 of 1

Interfacing two mojo boards

Posted: November 19th, 2015, 12:46 pm
by Nischal
Is it possible to interface two mojo boards?
One as a master and another as a peripheral.
Also with this interface is it possible for one mojo to handle all the communication with the computer?

Re: Interfacing two mojo boards

Posted: November 19th, 2015, 2:20 pm
by embmicro
Of course! There's nothing that would prevent this. You could use whatever protocol you wanted (SPI, UART, your own...) and then just have the two designs implement it.

The only thing is you would still need to plug each board into your computer to program it initially.

Re: Interfacing two mojo boards

Posted: November 19th, 2015, 2:35 pm
by Nischal
Thank you.
I have an other question.
I am trying to drive all the pins on the mojo and it so happens that 2 particular pins are not able to drive the Chip select signals(implementing SPI)
The problem repeats even if i change the mojo board itself.
Do you know if the drive strength drops when i try to use all the IO pins

Re: Interfacing two mojo boards

Posted: November 24th, 2015, 1:38 pm
by embmicro
There is a maximum amount of current you can pull through all the pins. If I remember correctly off the top of my head it is around 24mA per bank and 100mA for the entire chip. What are you connecting the pins to?

Re: Interfacing two mojo boards

Posted: November 24th, 2015, 1:44 pm
by Nischal
i am interfacing 48 LSM303D magnetic sensors mounted on PCBs.

Re: Interfacing two mojo boards

Posted: December 1st, 2015, 2:14 pm
by embmicro
You shouldn't have any trouble driving all the pins when connected to digital inputs. You'd run into trouble if you were trying to drive a ton of LEDs directly, but digital inputs take practically no current.

Have you tried measuring the pin's voltage? What behavior are you seeing?