V5 legacy 3-wire ports are supplied with voltage of 5V and have total maximum current limit of 2A shared between 8 ports (https://www.vexrobotics.com/v5-architecture.html#3-wire )
V5 smart ports, I believe, are 12V and have max current limit of 2.5A per motor or 20A/number_of_motors when you have more than 8 motors connected. That is likely enforced both by the motor firmware and eFuse on a V5 power distribution board .
Additional information regarding connecting third-party electronic components to V5 could be found in these threads:
Excellent question.
To my best knowledge, the pinout is as follows:
RS-485 A
RS-485 B
Power
GND
So if you manage to get a RJ11 crossover cable somewhere (or actually made one yourself, that’s much more likely occurence) and use it, you should still be good - as in, it won’t work, but nothing will burn.
RS-485 inputs need to be very resilient and high-enough input impedance anyway, so power into one of them is no big deal (the chips I have seen used survive ±70V, besides 16kV static discharg…
Yes, this is technically possible.
You should be able to use the Arduino’s PWM outputs coupled with an RC filter to create an analog voltage to send to the VEX Cortex (or V5 brain). Here’s a guide about RC filters: https://www.instructables.com/id/Arduino-RC-Circuit-PWM-to-analog-DC/ Note that the RC filter is necessary for this to work - you can’t just directly connect the Arduino PWM to the Cortex input.
You could also use the UART interface to send data from the Arduino to the Cortex (if th…
We are trying to figure out how to use a V5 port as a generic serial port in PROS, and have had little success.
As far as we can see, the main control functions PROS provides are serctl(), and registry_bind_port().
We can see how to bind the port with the second function, but are not sure how to go about reading the serial data from the port.
In the vex api there is a vexGenericSerialRecieve() function, where you pass in the port, and a buffer for the data. However, we cannot find an equivale…
Dear robotics programmers and enthusiasts,
VEX is amazing, and I feel like have learned a great deal in my past four years in VRC, especially about programming. The VEX hardware is fast and has external communication capability, and more and more tools are being put in place to program whatever can be imagined on VEX hardware. In order to more fully utilize these hardware abilities, I would like to showcase a new package I have developed.
Linked above are new ROS packages that allow VEX to …
I actually suggest using the USB port between the Raspi and the v5. It’s a lot easier and gives some fringe benefits. USB is a more robust communication system than running some uart line into the Raspi and doesn’t require any extra module or electronics.
You now get wireless downloading. You now get wireless pros terminal.
As a slightly more interesting approach, but still using an RPi, I’ve been working on the attached script that monkey patches pySerial allowing you to use all the standard pros commands from a host computer that then transmits serial requests over WiFi to a server running on the Pi. Because it pretends to be a serial device, things like uploading directly from a computer not the Pi work too (as well as serial terminal, etc.)