ESD Protection:
±
8kV air discharge
Serial interface 1 is connected to Q26 UART1 interface.
1.2.2
Serial port 2
This 8P8C (RJ45) modular connector provides RS232 or isolated RS485 interface for connecting to industrial
machines. A DIP switch is used to select between RS232 and isolated RS485 interface, and additional DIP
switches are used to enable or disable termination, pull-up and pull-down resistors. On the RS232 interface,
only 3 and 5 wires communication can be used.
Pin
Signal
1
RS485 B
2
RS485 A
3
RS485 GND
4
RS232 GND
5
RS232 RX
6
RS232 TX
7
RS232 CTS
8
RS232 RTS
ESD Protection:
±
8kV air discharge RS485 isolation: 1500Vrms, short-circuit and overvoltage protected.
Both RS232 and RS485 are connected to Q26 UART2 interface.
RS485 communication channel is half-duplex. The M2MBoxPro sets the transmission direction (sender or
receiver) automatically. When using RS485 the software needs to switch off the hardware flow control on
UART2 (AT+IFC=0,0).
1.2.3
Ethernet
There is one LAN interface on the M2MBoxPro. The interface transceiver is a ENC28J60 from Microchip. It is
directly connected to the Q26 SPI1 interface for data transfer, and also uses Q26 GPIO0 and GPIO25 signals
for reset and interrupt, respectively.
The transceiver is IEEE 802.3 Compatible , has integrated MAC and 10 BASE-T PHY, supports one 10BASE-T
port (full and half-duplex modes) through its 8P8C (RJ45) connector.
Two LEDs are available on the connector to check the communication status.
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3603-9, 36/F., 118 Connaught Road West, Sheung Wan, Hong Kong
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