Communication between cortexes

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#1

Connecting a cortex to another cortex and transferring data.

I am trying to create a set of robots; one will gather data from the surroundings and it will hand it over to the other robot, which will then perform a set of actions according to that data.

Is there a way to transfer data directly via cables?
or is there another efficient way to have the two cortexes communicate…

#2

https://vexforum.com/t/communicating-between-two-cortex-dual-cortex-robot/24236/1

#3

I am an introductory student, and don’t have enough deep knowledge about the subject…
Could you clarify a little bit more? Sorry

#4

Communication between 2 Cortexes is not designed to be terribly easy to do (no VEX programming software I’m aware of puts effort specifically into the process).

Read through jpearman’s post and the rest of the corresponding thread. Use the internet to help you: learn about UART.

Just be aware that if you were expecting a plug-and-play solution, you won’t be getting one.

#5

Since both Cortex microcontrollers are 3.3 Volt devices you could connect the TTL serial TX pin from Cortex #1 to the RX pin on the Cortex#2 and connect the RX pin from Cortex#1 to the TX pin on Cortex#2 using a shielded serial cable or use three wires of the same length but different colors. You need to also wire ground pins between both Cortex microcontrollers.

If using a Wireless UART was allowed, you could just connect each Cortex to an XBEE Pro module.

#6

So to kinda tie together what everyone is saying.

You need UART to do this. The command with be sendChar(5). To set this up you need to plug 1 of the 2 UART ports on each cortex into each other.

Wired setup would need 4 individual wires that have a male end on each side. Wire like this
GND - GND
TX- RX
RX-TX
VCC - VCC

And if you wanted to spend a little more on the project 2 of these 8$ chips could make the communication happen wirelessly

#7

Yes, that is correct, except you really don’t need to connect the VCC to VCC, since each Cortex has its own battery.

#8

If you use a wireless UART and it requires 3.3 Volts, then don’t connect it to the 3-wire Digital I/O ports or the motor ports or the Interrupt ports. They use 5 Volts. You would need a 3.3 volt regulator IC in between to supply the wireless UART power.

#9