Although the servo output of an RC receiver provides all the information required to control an L298N motor driver, the signal must be evaluated and recoded in a suitable manner , as the control logic of the motor driver is fundamentally different to that of an RC servo.
This task can be performed by the RCRX2Bridge II module.. This is a single-chip solution that evaluates one channel at a time and thus controls one motor of the L296 bridge.
With the new version of the module, the width of the range in which the motor is not driven — the hysteresis — can now be adjusted via a trimmer on the circuit board (see image). This now also allows support for simpler remote control receivers whose pulse widths fluctuate by more than 5 µs in the neutral position (up to a maximum of 100 µs with the trimmer turned fully to the left).
The circuit is very simple, and the breakout board already comes populated with all SMD components, so only the pin headers still need to be soldered. The assembly is both electrically and mechanically backward compatible with the first version of the RCRX2Bridge.
RCRX2Bridge II supports the two common, but different control modes of L298 bridges: Models with 2/4 phases and models with two logic inputs and one speed input.
Control of bridges with two inputs
The RCRX2Bridge II module is connected to the receiver on the input side, as shown in the featured image. The input pins of the motor driver IN1 and IN2 are connected to the output pins of the breakout board as shown in the featured image. If a second motor is to be controlled, then a second RCRX2Bridge II -module is required..
Control of bridges with three inputs
For this application, the RCRX2Bridge II module is configured for the changed logic using a solder bridge at “MODE” and then also connected to the receiver on the input side, as shown in the featured image.
The input pins of the motor driver ENA, IN1, and IN2 are connected to the output pins of the breakout board as shown in the image to the right. If a second motor is to be controlled, then a second RCRX2Bridge II -module is required.
The kit for the breakout board with the RCRX2Bridge II controller is available in the store.