Appearance and Hardware Configuration

Appearance Description

From top to bottom:

• C1 (Slot C1): 24ch 3.3V DIO
• C2 (Slot C2): 24ch 3.3V DIO
• C3 (Slot C3): 24ch 3.3V DIO
• C4 (Slot C4): 24ch 3.3V DIO

Interface Description

From left to right:

1. 24V DC Input
2. Protective Earth (PE)
3. LED Indicators
4. 10/100M Ethernet Port
5. Reset Button
6. FUNC Button (Located next to Reset)

LED Indicator Definition

Position	Name	Behavior Description
Top Left	Power	• Solid On: Power is on.
Top Right	Bootloader	• Blinks twice: Bootloader initialization no error at startup. • Solid On: Bootloader is running.
Bottom Left	Status	• Blinks twice: Main program initialization no error at startup. • Solid On: System is running. • Cyclic Blinking: Error occurred.
Bottom Right	OS	• Blinks at approx. 4 Hz: Ethernet cable connected. • Blinks at approx. 2 Hz: Ethernet cable not connected. • No Blink: OS stopped running.

Button Functions

Button	Function Description
Reset	• Short Press: Restart STEM. • Press simultaneously with FUNC: Restart and enter Bootloader mode.
FUNC	• Long Press 3 sec: Reset IP to default 192.168.1.110.