The 57R+ PLC option offers 50 I/O’s (18 inputs and 32 outputs). See Figures 57R+ I/O’s Datasheet p2 below, for general and technical features, and input, output, and communications details.


All Arduino Mega-based PLCs provide: two serial TTL (UART) services; and one each of I2C, SPI, RS-232, RS-485 (half or full duplex), and Ethernet services. All Raspberry PLCs provide: two each of RS-485 (half duplex) and Ethernet services; and one each of serial TTL (UART), I2C, SPI, Bluetooth, WiFi, and CAN bus services. Raspberry PLCs also provide four USB and one micro-HDMI sockets, plus real-time clock (RTC) and a microSD socket features. An I2C server may have up to 127 client nodes, which allows a network with more than 7,100 total relay, analog, digital, PWM, and interrupt I/O’s.

NOTE: The Arduino serial 0 service is shared with the USB port, which is designed for uploading and debugging only.


Six inputs are software configurable as either interrupts or digital. Twelve inputs are software configurable as either analog or digital.

NOTE: The digital and interrupt input voltage range is from 7 VDC to 24 VDC.
NOTE: The analog input voltage range is from 0 VAC to 10 VAC.
NOTE: If the M-Duino system is configured with the GPRS option, one digital/interrupt input is no longer available for use. See Figure 57R+ I/O’s GPRS / GSM Pinouts below.


Eight outputs are switch configurable as analog or digital/PWM (Pulse Width Modulation). Twenty-four outputs are relays.

NOTE: The digital/PWM output voltage range is from 5 VDC to 24 VDC, and the current limit is 70 milliamps.
NOTE: The analog voltage range is from 0 VAC to 10 VAC and the current limit is 20 milliamps.
NOTE: The relay outputs are open by default, the current limit is 5A for max 250 VAC, and the current limit is 3A for max 30 VDC.
NOTE: The PWM outputs are 5 Vdc; connecting these to components that require only 3 Vdc may damage those components.


See Figure 57R+ I/O’s Datasheet p3 below for Arduino quick start, safety precaution, and technical support contact information. Visit the Media –‍ PLCs –‍ M‑Duino and Media –‍ PLCs –‍ Raspberry pages for Datasheets, User Guides, and Videos.


These products offer the 57R+ I/O option (Relay / Analog / Digital / PWM / Interrupt).