====== MPINO-16A8R ====== MPINO-16A8R is a all-in-one industrial Arduino with 16 digital inputs and 8 relay outputs. A single PCB integrates 4 analog inputs, interrupt/encoder functions, I²C, and RS-232·RS-485·UART communication. Program the controller with Arduino IDE (Arduino C/C++) or MPINO STUDIO 2 (Arduino C/C++ & ladder logic). See the [[:en-us_products:mpino_series#mpino_series_specifications|MPINO Series specifications]] for the board name, connection method, and first I/O numbers for MPINO-16A8R. {{ :en-us_products:mpino-16a8r-connectors.svg?nolink |MPINO-16A8R connector guide }} ===== Product Specifications ===== ^ Category ^ Quantity ^ Terminal / Item ^ Specifications ^ | Power | - | Supply voltage | DC 9~12V (1A or more when using DC 12V) | | Digital inputs | 16 points \\ (Solid-state, isolated) | I(22)~I(37) | operating input voltage: DC 0~40V \\ HIGH detection voltage: DC 5V or higher \\ input resistance: 2.2kΩ \\ 8 points/1COM × 2 groups | | Relay outputs | 8 points \\ (Mechanical contacts, isolated) | R(39)~R(46) | operating connection voltage: DC 0~30V or AC 0~250V \\ maximum allowable output current: 5A/1 points, 15A/1COM \\ 4 points/1COM × 2 groups | | Analog inputs | 4 points \\ (Non-isolated) | A(0)~A(3) | Standard input: DC 0~5V, 10bit (0~1023) \\ Optional: DC 0~10V, 0(4)~20mA, NTC 10kΩ(25℃) \\ input resistance: 100MΩ(0~5V), 200MΩ(0~10V), 250Ω(0(4)~20mA) | | Interrupts \\ Encoder | 1 channel \\ (Non-isolated) | SDA(20) \\ SCL(21) | input voltage: DC 0~5V \\ Built-in 4.7kΩ pull-up resistor \\ I²C cannot be used simultaneously with the encoder | | Communication Channels | 1 channel \\ (Non-isolated) | I²C | I²C master/slave supported \\ Use SDA(20), SCL(21) | | ::: | ::: | RS-232 | Use ''Serial1'' \\ Built-in Modbus RTU Master & Slave commands supported \\ Built-in LS Industrial Systems Cnet commands supported | | ::: | ::: | RS-485 | Use ''Serial2'' \\ Automatic direction control supported \\ Built-in Modbus RTU Master & Slave commands supported \\ Built-in LS Industrial Systems Cnet commands supported | | ::: | ::: | UART | Use ''Serial3'' \\ Built-in Modbus RTU Master & Slave commands supported \\ Built-in LS Industrial Systems Cnet commands supported | | Memory | - | Flash | 256KB (including 8KB BootLoader) | | ::: | ::: | SRAM | 4KB | | ::: | ::: | EEPROM | 4KB | **Markdown file:** [[https://www.ilogics.net/docs/downloads:mpino:en:mpino_16a8r?do=export_raw|Download MPINO-16A8R.md]] ===== Digital inputs ===== [[:en-us_guide:wiring#digital_input_one_channel_check|See the one-channel digital-input check before wiring for the first time. →]] ^ Group ^ Terminal ^ Arduino Pin ^ Input Configuration ^ Terminals and Wiring Example ^ | COM0 | I(22)~I(29) | D22~D29 | 8 digital inputs, sharing COM0 | {{:en-us_products:mpino-16a8r-digital-input.svg?727|MPINO-16A8R digital input terminals and NPN/PNP wiring}} | | COM1 | I(30)~I(37) | D30~D37 | 8 digital inputs, sharing COM1 | ::: | The digital inputs are isolated by optocouplers and accept DC 5~24V NPN or PNP signals. Select the input type through the COM0·COM1 wiring polarity. ==== Example program · digital inputs ==== Use digitalRead() to display the D22~D37 input states every 200ms. HIGH is 1 and LOW is 0. void setup() { Serial.begin(115200); } void loop() { for (uint8_t pin = 22; pin <= 37; pin++) { Serial.print(F("D")); Serial.print(pin); Serial.print(F(": ")); Serial.println(digitalRead(pin)); } delay(200); } **Related built-in functions** === Function example · consecutive-read filter: IdigitalRead() === **Function prototype** bool IdigitalRead(uint8_t pin, uint8_t samples); IdigitalRead(22, 5) reads D22 5 times consecutively. Update the state when all readings are HIGH or all are LOW; mixed readings retain the previous state. Unlike a time-based debounce filter, it inserts no delay between readings. void setup() { Serial.begin(115200); } void loop() { const bool inputOn = IdigitalRead(22, 5); // Read D22 five times consecutively and return the stable state Serial.println(inputOn ? F("D22 ON") : F("D22 OFF")); delay(200); } === Function example · debouncing: Ibounce(), IbounceOn(), IbounceOff() === **Function prototype** bool Ibounce(uint8_t pin, uint32_t debounceTime); bool IbounceOn(uint8_t pin, uint32_t debounceTime); bool IbounceOff(uint8_t pin, uint32_t debounceTime); Compare three filters on the D22 input. Each returns the filtered ON/OFF state. * ''Ibounce(22, 30)'': Apply ON and OFF only after they remain stable for at least 30ms. * ''IbounceOn(22, 500)'': Delay ON by 500ms; apply OFF immediately. * ''IbounceOff(22, 500)'': Delay OFF by 500ms; apply ON immediately. Each function operates independently, even on the same pin. Run the filters on every loop() iteration and display only the results at 200ms intervals. unsigned long lastPrint = 0; void setup() { Serial.begin(115200); } void loop() { const bool stable = Ibounce(22, 30); // Filter D22 ON/OFF chatter over 30ms const bool onDelayed = IbounceOn(22, 500); // Delay only D22 ON by 500ms; apply OFF immediately const bool offDelayed = IbounceOff(22, 500); // Delay only D22 OFF by 500ms; apply ON immediately if (millis() - lastPrint >= 200) { lastPrint = millis(); Serial.print(F("Ibounce: ")); Serial.print(stable); Serial.print(F(", IbounceOn: ")); Serial.print(onDelayed); Serial.print(F(", IbounceOff: ")); Serial.println(offDelayed); } } === Function example · input toggle: Ialt() === **Function prototype** void Ialt(bool input, bool &state_var); Ialt(input, state) inverts state whenever the input changes from OFF to ON. Pressing D22 once turns D39 ON; pressing again turns it OFF. Holding the input retains the state. The example debounces the input with Ibounce(22, 30) before passing it to Ialt(). outputOn is a global variable retained between calls, and Ialt() modifies it directly. bool outputOn = false; void setup() { Serial.begin(115200); digitalWrite(39, LOW); } void loop() { const bool previous = outputOn; const bool inputOn = Ibounce(22, 30); // Filter D22 ON/OFF chatter over 30ms Ialt(inputOn, outputOn); // Invert outputOn on an OFF→ON input transition digitalWrite(39, outputOn ? HIGH : LOW); if (outputOn != previous) { Serial.println(outputOn ? F("D39 ON") : F("D39 OFF")); } } ===== Relay outputs ===== [[:en-us_guide:wiring#relay_output_one_channel_check|See the one-channel relay-output check before wiring for the first time. →]] ^ Group ^ Terminal ^ Arduino Pin ^ Contact ratings ^ Terminals and Wiring Example ^ | COM2 | R(39)~R(42) | D39~D42 | AC 250V or DC 30V, Max. 5A/1 points·15A/COM | {{:en-us_products:mpino-16a8r-relay-output.svg?850|MPINO-16A8R relay output terminals and load wiring}} | | COM3 | R(43)~R(46) | D43~D46 | AC 250V or DC 30V, Max. 5A/1 points·15A/COM | ::: | Relay outputs are dry contacts that physically connect COM2 or COM3 to each output terminal. Connect a separate load power supply. ==== Example program · relay outputs ==== Map inputs D22~D29 to outputs D39~D46 in order. When an input is HIGH, its corresponding output turns ON. void setup() { for (uint8_t pin = 39; pin <= 46; pin++) digitalWrite(pin, LOW); } void loop() { for (uint8_t ch = 0; ch < 8; ch++) { digitalWrite(39 + ch, digitalRead(22 + ch)); } } ===== Analog Input ===== ^ channel ^ Standard input ^ Option ^ Resolution ^ Connector Pinout ^ | A(0)~A(3) | DC 0~5V | DC 0~10V \\ 0(4)~20mA \\ NTC 10kΩ(25℃) | 10bit (0~1023) | {{:en-us_products:mpino-16a8r-analog-input.svg?439|MPINO-16A8R analog input connector pinout}} | Select the analog input range by changing the product's resistor configuration. ==== Example program · analog inputs ==== Use analogRead() to display the ADC raw values (0~1023) of A0~A3. Each channel's voltage/current mode follows the actual product settings. const uint8_t analogPins[] = {A0, A1, A2, A3}; void setup() { Serial.begin(115200); } void loop() { for (uint8_t ch = 0; ch < 4; ch++) { Serial.print(F("A")); Serial.print(ch); Serial.print(F(" ADC: ")); Serial.println(analogRead(analogPins[ch])); } delay(500); } **Related built-in functions** === Function example · input range scaling: IanalogRead(), IanalogReadf() === **Function prototype** int32_t IanalogRead(uint8_t ch, int32_t min, int32_t max); float IanalogReadf(uint8_t ch, float min, float max); Run this on products with A0 as the standard 0~5V input and A2 ordered as the 0(4)~20mA option. Both functions scale the ADC input to the specified min~max range. IanalogRead() returns an integer with the fractional part discarded; IanalogReadf() returns a floating-point value. This example displays the 0~5V input on A0 as both 0~100% and voltage. For the 0~20mA input on A2, specify a range of 0~20 to read the actual current. void setup() { Serial.begin(115200); } void loop() { const int32_t percent = IanalogRead(A0, 0, 100); // Scale A0 to an integer from 0~100% const float voltage = IanalogReadf(A0, 0.0f, 5.0f); // Scale A0 to a floating-point voltage from 0~5V const float current = IanalogReadf(A2, 0.0f, 20.0f); // Scale A2 to a floating-point current from 0~20mA Serial.print(F("A0: ")); Serial.print(percent); Serial.print(F(" %, ")); Serial.print(voltage, 2); Serial.print(F(" V, A2: ")); Serial.print(current, 2); Serial.println(F(" mA")); delay(500); } === Function example · 4~20mA range scaling: IanalogRead2(), IanalogRead2f() === **Function prototype** int32_t IanalogRead2(uint8_t ch, int32_t min, int32_t max); float IanalogRead2f(uint8_t ch, float min, float max); Run this on products with A0 as the standard 0~5V input and A2 ordered as the 0(4)~20mA option. Scale a 4~20mA sensor input connected to A2 to a user-defined range. IanalogRead2(A2, 0, 100) returns an integer with 4mA mapped to 0% and 20mA to 100%. IanalogRead2f(A2, 4.0f, 20.0f) returns the current as a floating-point value. Below approximately 3.6mA, both functions return ANALOG_READ2_ERROR(65535); from approximately 3.6~4mA, they return the specified minimum. void setup() { Serial.begin(115200); } void loop() { const int32_t percent = IanalogRead2(A2, 0, 100); // Scale A2 4~20mA to an integer from 0~100% const float current = IanalogRead2f(A2, 4.0f, 20.0f); // Convert A2 4~20mA to a floating-point current if (percent == ANALOG_READ2_ERROR || current == (float)ANALOG_READ2_ERROR) { Serial.println(F("A2: 4-20mA input error")); } else { Serial.print(F("A2: ")); Serial.print(percent); Serial.print(F(" %, ")); Serial.print(current, 2); Serial.println(F(" mA")); } delay(500); } === Function example · moving average: analogReadAvg(), analogRead2Avg() === **Function prototype** int32_t analogReadAvg(uint8_t ch, uint8_t samples); int32_t analogRead2Avg(uint8_t ch, uint8_t samples); Run this on products with A0 as the standard 0~5V input and A2 ordered as the 0(4)~20mA option. analogReadAvg(A0, 5) returns a moving average of the raw A0 ADC readings (0~1023). analogRead2Avg(A2, 5) averages the corrected A2 4~20mA values (4mA=0, 20mA=32767). Each function accumulates up to 5 valid readings from recent calls; it does not take 5 readings in one call. The maximum samples value is 20. analogRead2Avg() returns ANALOG_READ2_AVG_ERROR(-1) for inputs below approximately 3.6mA. void setup() { Serial.begin(115200); } void loop() { const int32_t voltageAvg = analogReadAvg(A0, 5); // Moving average of up to 5 recent A0 ADC values const int32_t currentAvg = analogRead2Avg(A2, 5); // Moving average of up to 5 recent corrected A2 4~20mA values Serial.print(F("A0 ADC average: ")); Serial.print(voltageAvg); Serial.print(F(", A2 4-20mA average: ")); if (currentAvg == ANALOG_READ2_AVG_ERROR) { Serial.println(F("input error")); } else { Serial.println(currentAvg); } delay(500); } ==== Example program · temperature sensor inputs ==== Run this only on products ordered with A0 configured as an NTC input. Use analogRead() to display the temperature-sensor ADC raw value (0~1023) of A0. Celsius conversion is explained in the built-in functions below. void setup() { Serial.begin(115200); } void loop() { Serial.print(F("A0 ADC: ")); Serial.println(analogRead(A0)); delay(500); } **Related built-in functions** === Function example · read NTC temperature: ntcRead(), ntcReadf() === **Function prototype** int ntcRead(uint8_t ch); float ntcReadf(uint8_t ch); Run this only on products ordered with A0 configured as an NTC 10kΩ input. Read the temperature of the NTC 10kΩ (25℃), B=3950K sensor connected to NTC input A0. ntcRead() returns an integer equal to 10 times the Celsius temperature (25.3℃ → 253); ntcReadf() returns the Celsius temperature as a floating-point value (25.3). Both have a resolution of 0.1℃. Values outside the conversion range are clamped to -40℃ or 120℃, so do not use these values to detect an open or short circuit. void setup() { Serial.begin(115200); } void loop() { const int temperature10 = ntcRead(A0); // Return A0 temperature as an integer in Celsius ×10 const float temperature = ntcReadf(A0); // Return A0 temperature as floating-point Celsius Serial.print(F("ntcRead: ")); Serial.print(temperature10); Serial.print(F(" (0.1 C), ntcReadf: ")); Serial.print(temperature, 1); Serial.println(F(" C")); delay(500); } ===== Interrupts / Encoder ===== ^ Function ^ Terminals / Arduino pins ^ channel ^ | External interrupts | SDA(D20), SCL(D21) | 2 points | | Encoder Inputs | Phase A: SDA(D20), phase B: SCL(D21) | 1 channel | | I²C | SDA(D20), SCL(D21) | 1 channel | SDA and SCL have built-in 4.7kΩ pull-up resistors. Encoder inputs and I²C use the same pins and cannot be used simultaneously. ==== Example program · pulse counting ==== Count FALLING edges on SDA(D20). The inputs have 4.7kΩ pull-ups (SDA/SCL). This software interrupt example reads the 32-bit value with ATOMIC_BLOCK and displays it every 500ms. Lossless counting is not guaranteed at the maximum input frequency. Because this uses SDA·SCL, do not run it simultaneously with I²C communication. static_assert(digitalPinToInterrupt(SDA) != NOT_AN_INTERRUPT, "Invalid interrupt input"); #include volatile uint32_t pulseCount = 0; void countPulse() { pulseCount++; } void setup() { Serial.begin(115200); // SDA is pulled up; count when the external signal pulls it to GND attachInterrupt(digitalPinToInterrupt(SDA), countPulse, FALLING); } void loop() { uint32_t snapshot; ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { snapshot = pulseCount; } Serial.print(F("SDA pulses: ")); Serial.println(snapshot); delay(500); } ==== Example program · encoder inputs ==== Connect phase A to SDA(D20) and phase B to SCL(D21). This x1 counting example uses a 4.7kΩ pull-up (SDA/SCL) and increments when phase B is LOW at a FALLING edge. The actual rotation direction depends on the phase A/B wiring. Because this uses SDA·SCL, do not run it simultaneously with I²C communication. static_assert(digitalPinToInterrupt(SDA) != NOT_AN_INTERRUPT, "Invalid interrupt input"); #include #include volatile int32_t position = 0; void readEncoder() { // Increment if phase B is LOW at the phase A falling edge (x1 decoding) if (digitalRead(SCL) == LOW) { if (position < INT32_MAX) position++; } else { if (position > INT32_MIN) position--; } } void setup() { Serial.begin(115200); // Encoder phase A → SDA(D20), phase B → SCL(D21) attachInterrupt(digitalPinToInterrupt(SDA), readEncoder, FALLING); } void loop() { int32_t snapshot; ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { snapshot = position; } Serial.print(F("Encoder: ")); Serial.println(snapshot); delay(500); } ===== Communication and Upload ===== ^ Function ^ Arduino Pin ^ Object ^ Device Wiring ^ | USB Upload / Monitoring | D0(RX0), D1(TX0) | ''Serial'' | {{:en-us_products:mpino-16a8r-communication.svg?780|MPINO-16A8R communication connectors and device wiring}} | | RS-232 | D19(RX1), D18(TX1) | ''Serial1'' | ::: | | RS-485 | D17(RX2), D16(TX2) | ''Serial2'' | ::: | | UART | D15(RX3), D14(TX3) | ''Serial3'' | ::: | | I²C | D20(SDA), D21(SCL) | ''Wire'' | ::: | RS-485 uses automatic direction control, so no separate control pin is needed to switch between transmission and reception. ==== Example program · basic communication ==== Forward characters between Serial(115200bps) and RS-232 Serial1(9600bps, 8-N-1). Check the free space in the transmit buffer with availableForWrite(). Serial2 is RS-485 and Serial3 is TTL UART; when using those terminals, replace Serial1 in the example with the corresponding object. // Serial Monitor via MP download cable ↔ RS-232 Serial1 void setup() { Serial.begin(115200); Serial1.begin(9600); // Also configure the other device for 9600 bps, 8-N-1 } void loop() { if (Serial.available() && Serial1.availableForWrite()) { Serial1.write(Serial.read()); } if (Serial1.available() && Serial.availableForWrite()) { Serial.write(Serial1.read()); } } ==== Example program · I²C communication ==== Use Wire to scan addresses 0x08~0x77 and display responding addresses every 3 seconds. Do not run this simultaneously with encoder/interrupt examples that use SDA·SCL. #include void setup() { Serial.begin(115200); Wire.begin(); Wire.setClock(100000); } void loop() { uint8_t found = 0; for (uint8_t address = 0x08; address <= 0x77; address++) { Wire.beginTransmission(address); const uint8_t result = Wire.endTransmission(); if (result == 0) { Serial.print(F("I2C: 0x")); if (address < 16) Serial.print('0'); Serial.println(address, HEX); found++; } } Serial.print(F("Devices: ")); Serial.println(found); delay(3000); } ==== Example program · Modbus RTU communication ==== **Related built-in functions** === Function example · Modbus RTU Slave: ImodbusRTUMem(), ImodbusRTUAdr(), ImodbusRTUInit(), ImodbusRTU() === **Function prototype** void ImodbusRTUMem(uint16_t m_size, uint16_t d_size); void ImodbusRTUAdr(uint16_t m_offset, uint16_t d_offset); void ImodbusRTUInit(HardwareSerial& serialPort, uint8_t slaveId, long baudrate); void ImodbusRTU(); Store the D22 state in M[0] and the raw A0 reading (0~1023) in D[0] for the other device to read. Configure RS-232(Serial1), station 1, 9600bps, 8N1. Read M[0] with FC01, start address 0, quantity 1 bit; read D[0] with FC03, start address 0, quantity 1 word. Addresses are zero-based on-wire addresses. Call the communication function on every loop() iteration. This example does not control outputs. M and D are shared global memory provided by the core. Run this sketch on its own. When combining protocols, do not allocate the shared memory more than once. For RS-485 terminals, replace Serial1 with Serial2; for UART terminals, use Serial3. unsigned long lastPrint = 0; bool memoryReady = false; void setup() { Serial.begin(115200); ImodbusRTUMem(8, 8); // Allocate 8 M bits and 8 D words ImodbusRTUAdr(0, 0); // Set the M and D communication start addresses to 0 ImodbusRTUInit(Serial1, 1, 9600); // Start RS-232 at station 1, 9600bps memoryReady = (M != nullptr && D != nullptr); if (!memoryReady) Serial.println(F("Memory allocation failed")); } void loop() { if (!memoryReady) return; M[0] = digitalRead(22); D[0] = analogRead(A0); ImodbusRTU(); // Process incoming Modbus RTU requests if (millis() - lastPrint >= 1000) { lastPrint = millis(); Serial.print(F("M[0]: ")); Serial.print(M[0]); Serial.print(F(", D[0]: ")); Serial.println(D[0]); } } === Function example · Modbus RTU Master: ImodbusRTUmasterInit(), ImodbusRTUmaster() === **Function prototype** void ImodbusRTUmasterInit(HardwareSerial& serialPort, long baudrate, uint8_t config); uint8_t ImodbusRTUmaster(HardwareSerial& serialPort, uint8_t slaveId, uint8_t functionCode, uint16_t address, uint16_t quantity, uint16_t* data, uint16_t timeoutMs = 100); Read one holding register from the remote slave over RS-232(Serial1) every 1 second. Configure the other device for station 1, 9600bps, 8N1, FC03, and on-wire start address 0. The response is stored in received[0] and displayed only on success. Error codes are displayed in hexadecimal. This is a separate sketch from the slave example above and uses a receive array instead of M/D memory. For RS-485 terminals, replace Serial1 with Serial2; for UART terminals, use Serial3. unsigned long lastRequest = 0; uint16_t received[1]; void setup() { Serial.begin(115200); ImodbusRTUmasterInit(Serial1, 9600, SERIAL_8N1); // Start RS-232 as a Modbus master } void loop() { if (millis() - lastRequest < 1000) return; lastRequest = millis(); const uint8_t result = ImodbusRTUmaster(Serial1, 1, 3, 0, 1, received, 200); // Read 1 word at address 0 from station 1, timeout 200ms if (result == IMODBUS_RTU_SUCCESS) { Serial.print(F("Register 0: ")); Serial.println(received[0]); } else { Serial.print(F("Modbus error: 0x")); Serial.println(result, HEX); } } ==== Example program · LS Industrial Systems Cnet communication ==== **Related built-in functions** === Function example · LS Industrial Systems Cnet SLave: ICnetMem(), ICnetAdr(), ICnetInit(), ICnet() === **Function prototype** void ICnetMem(uint16_t m_size, uint16_t d_size, uint16_t r_size = 100); void ICnetAdr(uint16_t m_offset, uint16_t d_offset, uint16_t r_offset = 0); void ICnetInit(HardwareSerial& serialPort, uint8_t slaveId, long baudrate); void ICnet(); Store the D22 state in M[0] and the raw A0 reading (0~1023) in D[0] for an HMI to read. Configure the other device for LS Industrial Systems Cnet, RS-232, station 1, 9600bps, 8N1. Read the bit at %MX00000(M[0]) and the word at %DW0(D[0]). Call the communication function on every loop() iteration. This example does not control outputs. M, D, and R are shared global memory provided by the core; this example does not use R. Run this separately from the Modbus example. When combining protocols, do not allocate the shared memory more than once. For RS-485 terminals, replace Serial1 with Serial2; for UART terminals, use Serial3. unsigned long lastPrint = 0; bool memoryReady = false; void setup() { Serial.begin(115200); ICnetMem(8, 8, 0); // Allocate 8 M bits and 8 D words; R is unused ICnetAdr(0, 0, 0); // Set the M and D communication start addresses to 0 ICnetInit(Serial1, 1, 9600); // Start RS-232 at station 1, 9600bps memoryReady = (M != nullptr && D != nullptr); if (!memoryReady) Serial.println(F("Memory allocation failed")); } void loop() { if (!memoryReady) return; M[0] = digitalRead(22); D[0] = analogRead(A0); ICnet(); // Process incoming LS Cnet requests if (millis() - lastPrint >= 1000) { lastPrint = millis(); Serial.print(F("M[0]: ")); Serial.print(M[0]); Serial.print(F(", D[0]: ")); Serial.println(D[0]); } } [[:en-us_products:mpino_series|← MPINO Series comparison (Korean)]]