from smbus2 import SMBus, i2c_msg
import struct
import time

# Beispiel: I2C-Adresse des Geräts
DEVICE_ADDRESS = 0x48  # z.B. EEPROM oder Sensoradresse
I2C_BUS = 1            # I2C-1 ist meist Standard beim Raspberry Pi

slot = input("Slot id (default: 0): ")
if slot == "": slot = 0
else: slot = int(slot)

def read_status(bus):
    data_to_write = [(0x06 | slot << 4)]

    write = i2c_msg.write(DEVICE_ADDRESS, data_to_write)
    bus.i2c_rdwr(write)

    # Lesen von 3 Bytes roher Binärdaten
    read = i2c_msg.read(DEVICE_ADDRESS, 8)
    bus.i2c_rdwr(read)
    data_read = bytes(read)
    print("data:", data_read.hex())

    data = struct.unpack("<HhHH", data_read)

    # data[0] is voltage in mV
    print(f"Spannung: {data[0]/1000:.2f}V, Strom: {data[1]}mA, Temperatur: {data[2]}°C, Error: 0x{data[3]:02X}")

with SMBus(I2C_BUS) as bus:
    # Schreiben von Rohdaten

    while True:
        
        print("Mögliche Aktionen:")
        print("  r <n>     n Zyklen lesen")
        print("  w <i>     i mA Strom positiv: laden (DAC), negativ entladen: (PWM)")
        act = input("nächste Aktion: ")
        if act[0] == "r":
            n = int(act.split(" ")[1])
            for i in range(n):
                time.sleep(1)
                try:
                    read_status(bus)
                except:
                    print("Bus error.")
        elif act[0] == "w":
            i = int(act.split(" ")[1])
            # 5 is the command for setting the current
            byte_str = struct.pack("<Bh", (5 + (slot << 4)), int(i))
            print("Sending bytes", byte_str.hex())

            write = i2c_msg.write(DEVICE_ADDRESS, list(byte_str))
            bus.i2c_rdwr(write)


        else:
            "Ungültiges Kommando."