.. _gateway-m-industrial-io:

Industrial I/O  (Example of a subsection within Industrial I/O)
-------------------------------------------------------------------

Your gateway features up to four industrial I/O expansion cards in order to support RS-232 (2-wire), RS-485 (half-duplex), CAN bus, or additional digital input/output channels. The following table illustrates industrial I/O functions and relevant ordering codes:

.. list-table:: Industrial I/O: functions and ordering codes
   :widths: 26 15 15 15 15
   :header-rows: 1

   * - FUNCTION
     - I/O SLOT A
     - I/O SLOT B
     - I/O SLOT C
     - I/O SLOT D
   * - RS-232 (2-wire)
     - ARS232
     - BRS232
     - CRS232
     - ---
   * - RS-485 (half-duplex)
     - ARS485
     - BRS485
     - CRS485
     - ---
   * - CAN bus
     - ---
     - ---
     - CCAN
     - ---
   * - Digital I/O (4x DI, 4x DO)
     - ---
     - ---
     - ---
     - DDIO

CAN Bus
^^^^^^^^^^^^

The device features up to 2 CAN 2.0B ports implemented with the processor's CAN controller. Note that the main CAN bus is always available, regardless of I/O module configuration. The second CAN bus is available if the expansion I/O module is installed.

RS-232
^^^^^^^^^^^^^^^

The RS-232 function is implemented with the MAX3221 (or compatible) transceiver interfaced with the
i.MX8M Plus processor UART ports. The key characteristics of this unit are:


* Support for TX/RX only
* Galvanic isolation from the main unit
* Programmable baud rate of up to 250 kbps

RS-485
^^^^^^^^^^^^

The RS-485 function is implemented with the MAX13488 (or compatible) transceiver interfaced with the i.MX8M Plus processor UART ports. The key characteristics of this unit are:

* 2-wire, half-duplex operation
* Galvanic isolation from the main unit
* Programmable baud rate of up to 3 Mbps
* Software-controlled 120Ω termination resistor

Digital inputs and outputs
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Four digital inputs are implemented with the CLT3-4B digital termination in accordance with EN 61131-2. Four digital outputs are implemented with the VNI4140K solid-state relay in accordance with EN 61131-2. The key characteristics of this system are:

* Designed for 24V PLC applications
* Galvanic isolation from main unit and other I/O modules
* Maximum current output of 0.5A per channel for digital outputs

.. list-table:: Digital I/O: Operating Conditions
   :widths: 46 10 10 10 10
   :header-rows: 1

   * - FEATURE
     - MIN.
     - TYP.
     - MAX.
     - UNIT
   * - External input voltage (24V_IN)
     - 12
     - 24
     - 30
     - V
   * - Input voltage: LOW level ($V_{IL}$ Max.)
     - 
     - 
     - 4
     - V
   * - Input voltage: HIGH level ($V_{IH}$ Min.)
     - 6
     - 
     - 
     - V

Industrial I/O terminal block
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

All industrial I/O module signals are routed to a terminal block. The pinout is determined by the configuration of I/O modules installed in the system.

.. list-table:: Industrial I/O: Terminal Block Specification
   :widths: 32 62
   :header-rows: 1

   * - **FEATURE**
     - **DESCRIPTION**
   * - Connector Type
     - 22-pin dual-raw plug with push-in spring connections
   * - Locking Mechanism
     - Screw flange
   * - Wire cross-section
     - AWG 20 - AWG 30


.. figure:: images/industrial_io_terminal_block.png
   :width: 45%
   :align: center

   Industrial I/O: Terminal Block Pinout


.. list-table:: Industrial I/O: Terminal Block Pinout
   :widths: 15 10 44 20
   :header-rows: 1

   * - **I/O MODULE**
     - **PIN**
     - **SIGNAL**
     - **ISOLATED POWER DOMAIN**
   * - A
     - 1
     - RS232_TXD / RS485_POS
     - 1
   * - ---
     - 2
     - CAN_L
     - 1
   * - A
     - 3
     - RS232_RXD / RS485_NEG
     - 1
   * - ---
     - 4
     - CAN_H
     - 1
   * - A
     - 5
     - ISO_GND_1
     - 1
   * - B
     - 6
     - RS232_RXD / RS485_NEG
     - 2
   * - B
     - 7
     - RS232_TXD / RS485_POS
     - 2
   * - B
     - 8
     - ISO_GND_2
     - 2
   * - D
     - 9
     - IN0
     - 3
   * - D
     - 10
     - IN1
     - 3
   * - D
     - 11
     - IN2
     - 3
   * - C
     - 12
     - RS232_TXD / RS485_POS / CAN_H
     - 3
   * - D
     - 13
     - IN3
     - 3
   * - C
     - 14
     - RS232_RXD / RS485_NEG / CAN_L
     - 3
   * - D
     - 15
     - OUT0
     - 3
   * - D
     - 16
     - OUT1
     - 3
   * - D
     - 17
     - OUT3
     - 3
   * - D
     - 18
     - OUT2
     - 3
   * - D
     - 19
     - 24V_IN
     - 3
   * - D
     - 20
     - 24V_IN
     - 3
   * - C/D
     - 21
     - ISO_GND_3
     - 3
   * - C/D
     - 22
     - ISO_GND_3
     - 3