A robust industrial-grade IO expansion HAT+ for Raspberry Pi 5, featuring isolated digital I/O, RS485, RS232, and seamless integration with the Argon Industria enclosure ecosystem.
The Cytron x Argon Industria Industrial IO HAT+ (SKU: ARG-IND-CYTRON) is a collaboration between Cytron and Argon 40, purpose-built to bring industrial-grade connectivity to the Raspberry Pi 5. It equips your Pi with the kind of robust, electrically isolated I/O found in factory automation, building management, and embedded industrial systems — all in a compact HAT+ form factor that slots directly onto the Pi's 40-pin GPIO header.
At its core, the board provides six isolated digital inputs (rated up to ±50V with 3750 Vrms isolation) and four isolated digital outputs (50V/500 mA per channel with 1500 Vrms isolation), alongside RS485 and RS232 serial interfaces for communicating with PLCs, sensors, and other industrial peripherals. Power is drawn from a wide-range DC 10–30V industrial supply — with surge protection up to 60V — so the board can coexist with the noisy power rails typical in industrial cabinets. An onboard 4-Amp replaceable fuse and isolated I/O keep your Raspberry Pi 5 protected from field wiring faults.
Designed as a first-class citizen within the Argon Industria ecosystem, the HAT+ is mechanically and electrically compatible with all Argon Industria HMI enclosures, from the compact 5C up to the 10CS. Optional support for the LetsTrust TPM module is built in for applications requiring hardware security. Whether you are building an HMI panel, a remote monitoring station, or an industrial automation controller, the Cytron x Argon Industria HAT+ provides a solid, well-specified hardware foundation.
📝 Note: This product is priced at $33.75 USD and is currently listed as sold out on argon40.com. Check the store page for restocking updates.
📝 Note: The following items are not confirmed in available documentation. Verify your shipment contents against the packing slip included in the box.
| Specification | Value |
|---|---|
| SKU | ARG-IND-CYTRON |
| Price | $33.75 USD |
| Form Factor | HAT+ (Raspberry Pi 40-pin standard) |
| Compatible Platform | Raspberry Pi 5 |
| RS485 Interface | 1× channel, max 1 Mbps, automatic direction control |
| RS485 UART Mapping | UART0 — TX: GPIO14, RX: GPIO15 |
| RS232 Interface | 1× channel, max 250 kbps |
| RS232 UART Mapping | UART4 — TX: GPIO12, RX: GPIO13 |
| Isolated Digital Inputs | 6 channels (DI0–DI5) |
| Digital Input Voltage Range | ±3V to ±50V (low level ≤ ±0.8V, high level ±3V to ±50V) |
| Digital Input Isolation Voltage | 3750 Vrms |
| Isolated Digital Outputs | 4 channels (DO0–DO3) |
| Digital Output Max Voltage | 50V |
| Digital Output Max Current | 500 mA per channel |
| Digital Output Isolation Voltage | 1500 Vrms |
| Power Input Voltage | DC 10–30V |
| Power Input Surge Protection | Up to 60V for 20 ms |
| Max Current to Raspberry Pi (5V rail) | 5A |
| Fuse Protection | 4-Amp, replaceable |
| Programmable LEDs | 2× (LED0: GPIO17, LED1: GPIO18) |
| Status LEDs (automatic) | RS485 activity, RS232 activity, DI0–DI5, DO0–DO3 |
| Active Buzzer | 1× programmable, GPIO23 (active high) |
| TPM Module Support | Optional — LetsTrust TPM module |
| Display Power Connector | 5V supply connector onboard |
| Operating Temperature | −20°C to +60°C |
| Operating Humidity | 10–80% RH (non-condensing) |
All GPIO references use Raspberry Pi 5 BCM numbering.
| Function | Raspberry Pi GPIO |
|---|---|
| DI0 | GP4 |
| DI1 | GP5 |
| DI2 | GP6 |
| DI3 | GP16 |
| DI4 | GP22 |
| DI5 | GP27 |
| DO0 | GP19 |
| DO1 | GP20 |
| DO2 | GP21 |
| DO3 | GP26 |
| RS485 TX | GP14 |
| RS485 RX | GP15 |
| RS232 TX | GP12 |
| RS232 RX | GP13 |
| LED0 | GP17 |
| LED1 | GP18 |
| Active Buzzer | GP23 |
| TPM RSTn | GP24 |
| TPM IRQn | GP25 |
| TPM CS0n | GP8 |
| TPM CS1n | GP7 |
| TPM MISO | GP9 |
| TPM MOSI | GP10 |
| TPM SCK | GP11 |
⚠️ Warning: The GPIO pins listed above are exclusively reserved by the HAT+. Connecting additional HATs, boards, or wiring that conflicts with any of these pins may cause unexpected behaviour or damage to connected devices. Verify GPIO availability before expanding your system.
The Cytron x Argon Industria Industrial IO HAT+ is designed exclusively for the Raspberry Pi 5. No other Raspberry Pi model is supported.
The Raspberry Pi 5 is the first Pi to feature the RP1 south-bridge chip, which provides dedicated hardware UART, SPI, and GPIO controllers that the HAT+ relies on for its RS485 (UART0), RS232 (UART4), and TPM (SPI) interfaces. Earlier Pi models do not expose UART4 and are not compatible.
The Raspberry Pi 5 is a compact, high-performance single-board computer featuring a 2.4 GHz quad-core 64-bit Arm Cortex-A76 processor — a significant step up from the Pi 4, and well-suited to demanding industrial HMI and control applications.
| Specification | Details |
|---|---|
| Processor | Broadcom BCM2712, 2.4 GHz quad-core 64-bit Arm Cortex-A76 |
| GPU | VideoCore VII, OpenGL ES 3.1, Vulkan 1.2 |
| RAM Options | 2 GB, 4 GB, 8 GB, or 16 GB LPDDR4X-4267 |
| Built-in Storage | None — microSD card required |
| Storage Expansion | microSD (UHS-I); PCIe 2.0 ×1 connector (M.2 HAT optional) |
| Wi-Fi | Dual-band 802.11ac (2.4 GHz + 5 GHz) |
| Bluetooth | 5.0 / BLE |
| Ethernet | Gigabit (1000 Mbps) |
| USB Ports | 2× USB 3.0 (5 Gbps), 2× USB 2.0 |
| Display Outputs | 2× micro-HDMI (up to 4Kp60 simultaneous), MIPI DSI, MIPI CSI |
| GPIO Header | 40-pin Raspberry Pi standard |
| Power Input | USB-C Power Delivery (PD) |
| Recommended PSU | 5V 5A (27W) USB-C PD |
| Minimum PSU | 5V 3A (15W) USB-C PD |
| Real-Time Clock | Yes — onboard RTC with battery connector |
| Power Button | Yes |
| Supported Operating Systems | Raspberry Pi OS (64-bit recommended), Ubuntu, other Linux distributions |
| Dimensions | 85 mm × 56 mm |
Source: raspberrypi.com
📝 Note: Although the Raspberry Pi 5 has a USB-C power input, in a typical Argon Industria installation the HAT+ provides power to the Pi through its 5V rail. Consult your enclosure assembly documentation to confirm the correct power routing for your build.
⚠️ Warning: Disconnect all power sources before handling the HAT+ or connecting any wiring. The HAT+ and its connected field wiring may carry voltages up to 50V on digital output lines. Always verify polarity and voltage levels before applying power.
Ensure your Raspberry Pi 5 is powered off and disconnected from any power source. If installing into an Argon Industria enclosure, follow the enclosure's base assembly instructions before proceeding.
Align the HAT+'s 40-pin female connector with the Raspberry Pi 5's 40-pin GPIO header. Lower the board evenly and press firmly until the connector is fully seated. The HAT+ should sit flush and level above the Pi with no visible gap in the connector.
⚠️ Warning: Misaligning the 40-pin connector and forcing the board can bend GPIO pins on the Raspberry Pi 5 and permanently damage both boards. Take care to align all pins before applying pressure.
Before connecting any power, confirm the 4-Amp replaceable fuse is correctly installed in its holder on the HAT+ PCB. A missing or blown fuse will prevent the board from powering on.
📝 Note: If the fuse holder is empty or you are unsure of the fuse condition, replace it with a new 4-Amp fuse before proceeding. [TODO: Obtain and document the specific fuse part number, voltage rating, and breaking capacity for replacement ordering]
Attach your digital input and digital output field devices to the pluggable IO terminal connectors on the HAT+:
Ensure all wires are securely clamped in the terminal connectors and that there are no loose strands that could cause short circuits.
⚠️ Warning: The digital inputs tolerate up to ±50V. Do not connect signals exceeding this limit. The isolation voltage (3750 Vrms for DI, 1500 Vrms for DO) protects the Raspberry Pi in fault conditions, but sustained overvoltage will damage the isolation barrier.
Attach your serial field devices to the appropriate terminal connectors:
📝 Note: RS485 and RS232 can be used simultaneously if your application requires both serial interfaces.
⚠️ Warning: RS485 wiring in industrial environments should use twisted-pair cable. Ensure cable shielding and termination resistors are used according to your network topology to prevent signal reflections, particularly at baud rates above 250 kbps.
Attach your DC power supply (10–30V) to the IO Terminal power input connector on the HAT+. Verify polarity carefully before connecting.
⚠️ Warning: Reversing power supply polarity may permanently damage the HAT+. Double-check positive (+) and negative (−) connections before applying power. The surge protection only covers transient overvoltage up to 60V for a maximum of 20 ms — sustained overvoltage beyond 30V will damage the board.
📝 Note: No earth (protective ground) connection is required by the power input, but earthing your enclosure is recommended practice in industrial installations.
If your application requires hardware security (e.g., secure boot, key storage, or TPM 2.0 attestation), insert the optional LetsTrust TPM module into the dedicated pin headers on the HAT+. The module uses the SPI interface and the following GPIO pins, which are pre-assigned on the HAT+:
| Signal | GPIO |
|---|---|
| RSTn | GPIO24 |
| IRQn | GPIO25 |
| CS0n | GPIO8 |
| CS1n | GPIO7 |
| MISO | GPIO9 |
| MOSI | GPIO10 |
| SCK | GPIO11 |
[TODO: Obtain and document the physical orientation and insertion direction for the LetsTrust TPM module on the HAT+ headers]
If you are integrating an Argon Industria HMI display, connect the display's power cable to the onboard 5V display power connector. This connector supplies 5V power to the display panel.
The HAT+ is mechanically and electrically compatible with the following Argon Industria enclosures:
[TODO: Obtain enclosure-specific wiring diagrams and assembly instructions for each compatible HMI enclosure, including any ribbon cables, display signal connections, or enclosure-specific mounting hardware]
Apply power to the DC input. Confirm the following: