RS485 Serial port
The SXPi is equipped with a RS485 serial port on a 4 pins terminal block:
Picture 9 – Terminal block for RS485 port
From this terminal block, it is possible to withdrow a power line with the same voltage of the main power
supply input, rectified in case of AC input, and with a max current of 200mA.
The RS485 serial port is accessible by the Linux System on the device:
/dev/ttyUSB1
.
Electrical features of the RS585 serial port:
-Driver Output Capability ±60mA Max
-Receiver Input Impedance 12KOhm Min
-Receiver Input Sensitivity ±200mV
-Receiver Input Hysteresis 50mV Typ
-From Single 5-V Supply
Signalling LEDs
Placed on top of SXPI, there are two LEDs. A yellow one directly connected to and controlled by the Telit
modem and another a bi-color one controlled by the ARM processor.
Picture 10 – Signalling LEDs
Device
GPIO Raspberry Pi
PIN Raspberry Pi
LED Red
27
13
LED Green
17
11
User Manual SXPi
Page 6
