ME910C1 HW User Guide
1VV0301351 Rev.8 Page 51 of 99 2018-09-28
SPI Connections
5.7.3. Serial Ports
The ME910C1 module is provided with by 2 Asynchronous serial ports:
• MODEM SERIAL PORT 1 (Main)
• MODEM SERIAL PORT 2 (Auxiliary)
Several configurations can be designed for the serial port on the OEM hardware, but the
most common are:
• RS232 PC com port
• microcontroller UART @ 1.8V (Universal Asynchronous Receive Transmit)
• microcontroller UART @ 5V or other voltages different from 1.8V
Depending from the type of serial port on the OEM hardware a level translator circuit may
be needed to make the system work. On the ME910C1 the ports are CMOS 1.8.
5.7.3.1. Modem serial port 1
The serial port 1 on the ME910C1 is a +1.8V UART with all the 7 RS232 signals. It differs
from the PC-RS232 in the signal polarity (RS232 is reversed) and levels.
The following table is listing the available signals: