User's Guide

ME910C1 HW User Guide
1VV0301351 Rev. 2 Page 46 of 81 2017-07-19
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.
5.6.2.2. Modem serial port 1 (USIF0)
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:
RS232
Pin
Signal PAD Name Usage
1 C109/DCD
N14
Data Carrier Detect
Output from the ME910C1
that indicates the carrier
presence
2 C104/RXD
M15
Transmit line *see
Note
Output transmit line of
ME910C1 UART
3 C103/TXD
N15
Receive line *see Note
Input receive of the ME910C1
UART
4 C108/DTR
M14
Data Terminal Ready
Input to the ME910C1 that
controls the DTE READY
condition
5 GND
M12
,
B13,
P13,
E14
Ground Ground