Terminal block pin
Signal
1
SCL
2
SDA
3
GND
4
+2.8V
When facing the connector, with the M2MBoxPro LED up, the pin 1 is the leftmost pin.
ESD Protection: +
±
8kV air discharge
In the I²C bus, the M2MBoxPro is always the master, and the mximum transfer speed: 400kbps. For more
information on the bus, refer to “I²C bus specifications version 2.0” from PHILIPS.
The 2.8V reference voltage can be deactivated using one of the M2MBoxPro configuration DIP switches.
1.2.10
Analog Inputs
There are two external analog inputs on the screw terminal blocks of the M2MBoxPro, and two more internal
analog inputs for temperature and voltage sensor. The analog inputs can be either voltage or current inputs,
controlled by two jumper switches. The analog inputs are protected with self-resettable fuses and transient
protection diodes. Analog inputs are multiplexed, and the multiplexer address is set with Q26 GPIO 20 and
GPIO 21 signals. To read the value of the inputs, please refer to the following table:
Analog signal
GPIO20
GPIO21
0
0
0
1
1
1
Temperature
0
1
Voltage
1
1
The selected analog channel is then available on the ADC input of the Q26 processor. For temperature sensors
and voltage sensor specifications, refer to corresponding sections of this document.
Analog voltage range: 0-10V Analog current range: 0-20mA
ADC resolution: 10bits
Protections fuse rating: 80mA
Maximum peak power: 600 Watts (10/1000 ms)
1.2.11
Digital Outputs
The M2MBoxPro features 4 digital open collector outputs.
The outputs are connected to Q26’s GPIO22, GPIO23, GPIO24 and GPIO35 signals. They are opto-isolated
and have an integrated fly-back protection diode
Isolation: 3750Vrms
Maximum base-collector voltage: 160V
Maximum continuous current: 600mA
Maximum power dissipation: 350mW at up to 25°C, derate at 2.8mW/°C above 25°C
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