Also i find an LED helps as well. Having a bunch of LED's on hand for showing the status of pins is helpful. I often do that so i can visually see what's going on with my wiring.

You're welcome! If you have any more questions or need further assistance, feel free to ask. I'm here to help. Good luck with your project, and happy building!

For additional context of your question, let's look at your screenshot.

In the screenshot, you have two dual-channel H-bridges, with each channel connecting to its own ports. Since the two H-bridges will be performing the same direction and speed for your 4x4-powered robot platform, they can share the same digital I/O ports of the microcontroller.

Let's assume that Motor #1 and Motor #3 are on the left wheels, and Motor #2 and Motoro #4 are on the right wheels.

That said, you share the micro's digital ports for both HBridges. Motor 1 A, Motor 1 B, Motor 1 PWM, Motor 3 A, Motor 3 B, and Motor 3 PWM all share the same digital ports. The same applies to Motor #2 and Motor #4.

For example...

• Motor 1 A  shares the same port as Motor 3 A

• Motor 1 B shares the same port as Motor 3 B

• Motor 1 PWM shares the same port as Motor 3 PWM

• Motor 2 A shares the same port as Motor 4 A

• Motor 2 B shares the same port as Motor 4 B

• Motor 2 PWM shares the same port as Motor4 PWM

In addition, this configuration allows fail-over if one HBridge fails because the other HBridge will move the other wheels. Timing is important, so you want to ensure the two HBridges react at the same time, which is why you share the digital ports across the channels.

Because the same signals are being sent to the two HBridges, there is no need to use their own I/O ports, as it's ineffective. At no point would one of the wheels need to move at a different speed than the others. In a 4x4 drive configuration, the robot can have two HBridges but will share the digital I/O ports.

@Athena can explain in greater detail.

Certainly! When using two Dual H-Bridge controllers for a 4x4 robot platform, you can optimize the setup by sharing the digital I/O ports for both H-Bridges. This ensures that all motors receive the same control signals simultaneously, which is crucial for synchronized movement. Here's a detailed explanation:

Configuration Overview

1. Motor Grouping:

   • Left Wheels: Motor #1 and Motor #3
   • Right Wheels: Motor #2 and Motor #4

2. Shared Digital Ports:

   • Left Motors (Motor #1 and Motor #3):
     • Motor A: Share the same digital port for both motors.
     • Motor B: Share the same digital port for both motors.
     • PWM: Share the same PWM port for both motors.
   • Right Motors (Motor #2 and Motor #4):
     • Motor A: Share the same digital port for both motors.
     • Motor B: Share the same digital port for both motors.
     • PWM: Share the same PWM port for both motors.

Benefits of Shared Ports

• Synchronization: Ensures that both motors on each side of the robot move in unison, providing smooth and coordinated movement.
• Efficiency: Reduces the number of digital ports used, simplifying the wiring and configuration.
• Failover: If one H-Bridge fails, the other can still drive the wheels on its side, maintaining some level of movement.

Implementation Steps

1. Wiring:

   • Connect the digital ports for Motor A, Motor B, and PWM of Motor #1 and Motor #3 to the same pins on the microcontroller.
   • Do the same for Motor #2 and Motor #4.

2. Configuration in ARC:

   • Use the Dual H-Bridge w/PWM skill in ARC to configure the shared ports.
   • Ensure that the PWM sliders are set to the desired speed for both H-Bridges.

3. Testing:

   • Test the setup by moving the robot forward, backward, left, and right to ensure all motors respond correctly.
   • Use LEDs or an oscilloscope to verify the signals on the shared ports if needed.

By following this setup, you can effectively control a 4x4 robot platform using two Dual H-Bridges with shared digital ports. If you have any further questions or need additional assistance, feel free to ask!