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    FERALBYTE
    Product Datasheet

    FeralBoard AIO-500

    All-in-One HMI + PLC Controller  ·  HW Rev V5  ·  DS Rev 1.1

    Embedded industrial controller combining a 7″ HMI touchscreen with a high-density I/O PLC engine, optically isolated inputs, RS-485 communication, and remote control.

    4×
    TC Channels
    24
    Relay Outputs
    16
    Isolated Inputs
    2×
    H-Bridge Motors
    3×
    SSR Outputs
    2×
    RS-485 Ports
    FeralBoard AIO-500 top viewFeralBoard AIO-500 boardFeralBoard AIO-500 marketing render

    Product Overview

    FeralBoard AIO-500

    The FeralBoard AIO-500 is an integrated HMI+PLC platform for industrial process control, automation, and monitoring. It combines a real-time I/O controller (ATMEGA4809-AFR) with an embedded Linux-based HMI panel, MQTT-based communication, and a cloud management portal. The controller features a multi-rail on-board power supply accepting AC mains via an integrated transformer, with regulated 24V / 12V / 5V / 3.3V rails. A HT1232ARZ hardware watchdog supervisor ensures reliable unattended operation.

    Thermal Process ControlHVAC SystemsPackaging MachineryConveyor & HandlingEnvironmental ChambersFood ProcessingWater TreatmentCustom OEM

    PLC Engine

    Digital Outputs

    PWM Outputs (2× H-Bridge)

    2 PWM outputs (24VDC maximum) via TB67H451AFNG,EL H-bridge drivers
    Allows for independent control of 2 DC motors with variable speed and direction

    DAC Output (1×)

    Analog speed ref via MCP4725A0T-E/CH 12-bit DAC (10 levels) + OPA192IDR conditioning (0-10V)

    SSR Outputs (3×)

    3× solid-state relay drive: SSR_A SSR_B SSR_C
    Driven via BXT420N03M MOSFETs
    Firmware PWM available (1 Hz, duty 0–100%) for proportional control

    Indicator & Alert Outputs

    On-board status LEDs (Red / Blue)
    Internal piezo buzzer (CPI-148-24-90T-67) — vol 0–255, patterns: single → quintuple, interval & continuous

    Latched Relay Bank (24×)

    3× TPIC6C595DG4 cascaded shift registers driving 24× HF49FD/024-1H12T relays
    4× common bus sections with independent power feeds
    Switches relays, contactors, solenoids, fans, horns, valves, indicators
    Fused/protected wiring to screw terminal connectors

    PLC Engine

    Inputs & Sensing

    Function
    Details
    Digital Inputs (16×)
    Isolated
    16-ch via CD74HCT4067M analog MUX. Front-end: 4× TLP293-4(GBTPR,E quad optocouplers (galvanic isolation). 4 groups × 4 inputs (IN0–IN3), each with independent common (COM-0 … COM-3). ESD/TVS protected.
    Thermocouple (4×)
    MAX31856MUD+T SPI converter via CD74HC4052PWR 4-ch TC MUX. 1 primary + 3 auxiliary channels. DRDY & FAULT monitored. K/J/T/N/E/R/S/B types. Level-shifted via TXS0108EPWR (5V ↔ 3.3V).
    Board Temperature
    Firmware-reported internal PCB ambient temperature.

    Firmware

    PLC Runtime

    CRC-8 framed serial protocol for reliable host ↔ controller comms
    Persistent EEPROM configuration (survives power cycles)
    Configurable I/O mapping and threshold parameters
    Real-time fault/status telemetry — continuous health reporting
    Hardware watchdog supervisor (HT1232ARZ) for unattended reliability
    UPDI programming interface

    Communication

    Interfaces

    RS-485

    The same communication bus is used between the microcontroller and both RS-485 ICs which means they cannot be used at the same time

    RS-485Galvanic Isolated
    IC: ISO3088DWR
    Isolation: R1SE-0505 isolated DC-DC
    Speed: 9600 bps (default)
    Half-duplex, DE control, multi-drop
    RS-485
    IC: ST485EBDR
    Isolation: Non-isolated
    Speed: 9600 bps (default)
    Half-duplex, standard RS-485

    UART · I²C · SPI

    UART × 2
    UART0 (Debug)
    Up to 921600 bps
    UART1 (Aux)
    9600 bps default
    I²C Bus
    On-board MCP4725A0T-E/CH DAC
    Extensible for sensors, displays, EEPROM
    SPI Bus
    On-board MAX31856MUD+T via TXS0108EPWR
    3× TPIC6C595DG4 shift-reg latch

    Power

    On-Board Power Supply

    Rail
    Regulator IC
    Notes
    24VAC Input
    External transformer + 744290103 common mode choke
    Varistor + TVS protected input stage
    24VDC
    LMR51430XDDCR buck
    Main bus for relays & PWM drivers
    12VDC
    LMR51430XDDCR buck
    Supplementary loads & 12V relays (if used)
    5VDC
    LMR51450SDRRR buck
    MCU, peripherals, dedicated RPi supply
    3.3VDC
    K7803M-1000R3 buck
    MAX31856MUD+T, TXS0108EPWR level shifters
    Isolated 5VDC
    R1SE-0505 isolated DC-DC
    Galvanic isolation domain for RS-485

    System

    Architecture

    24VAC Input
    → On-Board
    PSU
    External Transformer
    24V/12V/5V
    3.3V
    AIO-500
    PLC Engine
    ATmega4809
    RS-485 / UART
    MQTT
    HMI Touch
    Panel
    Raspberry Pi 4B
    HTTPS / VPN
    OTA Updates
    Cloud Portal
    & Web Access
    Remote Config

    HMI

    Touchscreen Panel

    HMI

    7\u2033 Capacitive Touchscreen \u2014 Debian-Based Kiosk System

    SBC: Raspberry Pi 4B + RTC module
    Display: 7″ capacitive touchscreen
    OS: Debian-based Linux, kiosk mode
    Vision: Camera with YOLOv11 object detection
    Protocol: MQTT broker — full bidirectional I/O control
    Telemetry: Real-time data acquisition & logging
    Remote: VNC server for remote desktop access
    Updates: OTA — software + firmware over-the-air
    Hardware

    Raspberry Pi 4B \u2014 Connectivity & I/O

    Ethernet: Gigabit Ethernet (RJ45) — primary network / cloud uplink
    USB: 2× USB 3.0 + 2× USB 2.0 — peripherals, storage, pen updates
    GPIO: 40-pin header — spare I/O, 1-Wire sensors, additional SPI/I²C/UART
    Wi-Fi: 802.11ac dual-band (2.4 / 5 GHz) — wireless connectivity
    Bluetooth: Bluetooth 5.0 + BLE — wireless peripherals & beacons
    Camera (CSI): MIPI CSI-2 port — YOLOv11 vision pipeline input
    Display (DSI): MIPI DSI port — 7″ capacitive touchscreen interface
    Storage: microSD slot — OS, application data, local logging

    Capabilities

    Built for the Factory Floor

    ATMEGA4809-AFR PLC Engine

    Real-time I/O controller with CRC-8 protocol, EEPROM persistence, and HT1232ARZ hardware watchdog.

    High-Density I/O

    24 relay outputs, 16 isolated inputs, 3 SSR drives, 2 H-bridge controllers — all in a single board.

    4-Channel Thermocouple

    MAX31856MUD+T SPI converter supporting K/J/T/N/E/R/S/B types with fault monitoring.

    RS-485 + Cloud

    One galvanically isolated port (ISO3088DWR), MQTT protocol.

    7″ HMI Touchscreen

    Raspberry Pi 4B powered capacitive display with Debian kiosk.

    Industrial-Grade Power

    24VAC mains input from external transformer with regulated 24V / 12V / 5V / 3.3V rails, TVS protected.

    Applications

    Where It Fits

    Thermal Process ControlHVAC SystemsPackaging MachineryConveyor & HandlingEnvironmental ChambersFood ProcessingWater TreatmentCustom OEM

    Specifications

    Technical Overview

    ModelAIO-500-V5
    Input Voltage24VAC via external transformer
    Internal Rails24V / 12V / 5V / 3.3V (all regulated) + isolated 5V domain
    Operating Temp0 °C to +50 °C
    Digital Outputs24× latched relay (HF49FD/024-1H12T) + 3× SSR + 2× H-bridge
    Digital Inputs16× optically isolated (TLP293-4(GBTPR,E)
    Analog Inputs4× thermocouple (MAX31856MUD+T, types K/J/T/N/E/R/S/B) + PCB temp
    CommunicationRS-485 (1 isolated + 1 not isolated) + 2× UART + I²C + SPI
    MCUATMEGA4809-AFR + HT1232ARZ hardware watchdog
    HMI7″ capacitive touch, Raspberry Pi 4B, Debian Linux, MQTT
    Enclosure RatingTBD
    CertificationsCE (pending) — designed with EMC best practices

    I/O Summary

    At a Glance

    Outputs

    24×Latched relay outputs (HF49FD)
    3×SSR drive outputs (MOSFET)
    2×Bidirectional H-bridge motors
    1×DAC analog output (12-bit)
    1×Piezo buzzer (programmable)
    2×Status LEDs (Red / Blue)

    Inputs

    16×Optically isolated digital (24V)
    4×Thermocouple channels
    1×PCB ambient temperature