EMU Dual H-Bridge for Window Position Control

OTHER DEVICES
1

Hello everybody,

I am using the Dual H-Bridge as a position controller for my window regulator motor. My configuration in the “Ecumaster Light Client” is generally as follows:
Control Inputs → DIR1A: Position Control 1, PWM1: Position Control 1.
For Position Control 1 settings:
Setpoint Source: CAN Byte B1
Position Source: Analog Input 1.

In this setup, the Dual H-Bridge functions as a window control unit that receives the actual position from a potentiometer mounted on the window. The analog inputs of the Dual H-Bridge are used for this purpose. The target position and general logic are provided by a different control unit via CAN.

Overall, this setup works well, but I am facing two problems that I cannot solve:

  1. Startup position issue:
    At the moment the Dual H-Bridge starts up, the actual position signal from the potentiometer (which is connected to the Dual H-Bridge input) is not yet recognized. I believe the controller then uses Position 0 as the setpoint. This causes a short, unintended motor movement at vehicle startup, which can result in an overcurrent condition if the window is already at its maximum position.
    Is there any way to prevent this — for example, by disabling control until a valid position signal is available?

  2. Residual PWM at standstill:
    When the window is at a standstill position, the controller outputs a slight PWM signal (about 1–3%). Although this PWM does not move the window, it produces a noticeable sound from the motor current.
    Is there a way to introduce an offset (e.g., 0–10% PWM deadband) or disable the PID controller at standstill?

I would appreciate any advice or suggestions on how to address these issues.
Thank you very much for your help. And if there is currently no way to address these issues, would it be possible to release a firmware update that could resolve them?