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Document MT0605P.2018.E
© Xsens Technologies B.V.
MTi User Manual
6.4 Serial Connection Settings
6.4.1 Serial or USB communication
The MTi has a parallel serial (RS232/RS422/RS485 or alternative UART) and USB interface. However,
it is not possible to have communication on both the serial and USB interfaces simultaneously.
Therefore, the MTi wakes up as a serial device, unless USB is detected. When a USB interface is
detected, the communication will be done via that USB interface.
Default settings for serial connection can be found in [LLCP].
6.4.2 Transceiver voltage levels
The MTi’s RS232 transceiver has RS232 compliant output levels and is compatible with TIA/EIA-232-F
specifications. The MTi's RS485/RS422 transceiver has RS485 compliant output levels and is
compatible with TIA/EIA-485-A specifications. The differential lines of the RS422/RS485 communication
are terminated with a 120Ω resistor.
For completeness, the input and output voltage levels are listed below:
Table 17: Transceiver voltage levels
Low value (binary 1)
High value (binary 0)
RS232 RX (sensor)
7
< 0.8 V
> 2.5 V
RS232 TX (sensor)
< -5.0 V
8
> 5.0 V
9
RS422/RS485 RX (sensor)
10
Differential
< -0.2 V
> 0.2 V
RS422/RS485 TX (sensor)
11
Differential
< -2 V
> 2 V
7
typical hysteresis is 0.4V
8
typical value @ 25ºC and load of 3kΩ is -5.7 V
9
typical value @ 25ºC and load of 3kΩ is 6.2 V
10
typical hysteresis is 25mV
11
with a total differential load resistance of 50Ω (MTi already has 120Ω termination resistance)
