Telit Wireless Solutions ME910G1, Руководство по конструкции

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ME910G1 Hardware Design Guide
1VV0301593 Rev.12
Page 46 of 93 2021-09-24
Not Subject to NDA
Serial Ports
The ME910G1 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 on the type of serial port on the OEM hardware a level translator circuit may
be needed to operate the system. The ports on the ME910G1 the port are CMOS 1.8.
Modem Serial Port 1 (USIF0)
The serial port 1 on the ME910G1 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 lists the available signals:
RS232
Pin
Signal PAD Name Usage
1 C109/DCD N14 Data Carrier Detect
Output from the ME910G1 that indicates
the carrier presence
2 C104/RXD M15 Transmit line *see Note Output transmit line of ME910G1 UART
3 C103/TXD N15 Receive line *see Note Input receive of the ME910G1 UART
4 C108/DTR M14 Data Terminal Ready
Input to the ME910G1 that controls the
DTE READY condition
6 C107/DSR P14 Data Set Ready
Output from the ME910G1 that indicates
the module is ready
7 C105/RTS L14 Request to Send
Input to the ME910G1 that controls the
Hardware flow control
8 C106/CTS P15 Clear to Send
Output from the ME910G1 that controls
the Hardware flow control
9 C125/RING R14 Ring Indicator
Output from the ME910G1 that indicates
the incoming call condition
Table 22: Available Signals