import numpy as np
import matplotlib.pyplot as plt
from scipy.signal import TransferFunction, step

def step_rc(R, C, t_end, step_amplitude):
    # Define the transfer function H(s) = 1 / (RCs + 1)
    num = [1]
    den = [R * C, 1]
    system = TransferFunction(num, den)

    # Generate time points
    t = np.linspace(0, t_end, 1000)
    
    # Calculate the step response
    t, response = step(system, T=t)
    
    # Scale the response by the step amplitude
    response *= step_amplitude
    
    # Plot the step response
    plt.plot(t, response)
    plt.title('Step Response of RC Circuit')
    plt.xlabel('Time (s)')
    plt.ylabel('Response (V)')
    plt.grid(True)
    plt.show()
    
    return t, response

# Example usage
R = 1000  # Ohms
C = 1e-6  # Farads
t_end = 0.01  # seconds
step_amplitude = 5  # Volts

t, response = step_rc(R, C, t_end, step_amplitude)