@Vinny @Alex-Kushleyev This is all really helpful. Thank you! But I want to make clear what I need.
I have a VOXL 2 that I want to connect to a device with the following requirements:
- This device requires 16 GPIO Pins at 3.3V to operate.
- The VOXL2 also needs to have a constant connection to WiFi.
- Minimal time between function call and actuation of the GPIO Pin
- Minimal additional software (drivers, etc) that needs to be written (ideally there is an SDK I can use with the board(s))
The controller code for the device on the VOXL2 makes the following function call: "Pin X to Hi/Lo". For a bit clearer understanding, here is a rough schematic of what I need:

The Developer Test Board will do the entire thing for me without any additional software or B2B connections provided it has enough available GPIO pins at the required voltage. If it cannot acheive this, I need some insight into the following:
- A connector that adapts the proprietary connectors on the VOXL 2 to something more widely used (USB Mini B is an example).
- The correct port (JX) that will allow me to directly command the GPIO board (Like J5 or J3, etc)
- Advice on which boards will play well with the VOXL2 and can be commanded from the VOXL2 like gpio_write(PIN,HI/LO) with minimal additional software. (An example of what I need could be this board.
I understand that this sounds a lot like UART which could be a viable solution. However, I do not know if UART-enabled boards are fast and require no custom software scripts to be setup.
Please let me know if you need anything clarified. Thanks again!