Atom S3 Lite Rs485 Modbus Register 35002: Internal MOS2 Temperature

Technical Definition

The register Internal MOS2 Temperature at address 35002 is used to monitor internal mos2 Temperature on the Atom S3 Lite Rs485.

• Protocol: Modbus RTU
• Data Type: S WORD
• Unit: °C
• Access: Read Only

How to Read (Python pymodbus)

Use this code snippet to read this specific value via RS485:

from pymodbus.client.sync import ModbusSerialClient

client = ModbusSerialClient(method='rtu', port='/dev/ttyUSB0', baudrate=9600)
client.connect()

# Read Internal MOS2 Temperature (Address: 35002)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=35002, count=2, unit=1)

if not result.isError():
    print(f"Raw Value: {result.registers}")
else:
    print("Error reading register")

client.close()

Integration (Home Assistant)

Paste this into your configuration.yaml:

- platform: modbus_controller
  name: "Internal MOS2 Temperature"
  address: 35002
  value_type: S_WORD
  unit_of_measurement: "°C"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Atom S3 Lite Rs485]

    PLC -- "A+ (D+)" --> Device
    PLC -- "B- (D-)" --> Device
    PLC -- GND --> Device

💡 Engineer's Insight

Analysis: Temperature of MOS2 component within the Atom S3 Lite, measured in degrees Celsius. Monitors second critical power semiconductor.

Troubleshooting: Potential MOS2 failure, insufficient heat dissipation, or faulty Temperature sensor.