Convert one interface to another cables scheme
i.e. this cable may be used for wiring cellular phone to PC
universal mobile cellular cable or data-cable

Microcontrollers serial port (often called a SCI, COM, or ASYNC port) often do not generate the proper voltages required for connecting to computer RS-232 serial port. In this case special converter needed. Most microcontrollers run on a single supply voltage, that is usually +5 volts. In rough terms, logical 1 on these devices indicates that +5 is the voltage on the output pin. Logical 0 specifies that 0 volts is on the line.

The RS-232-C standard specifies that the voltage on the wire for sending a logical 0 are from +5v to +15v. The voltage for sending a 1 are from -5v to -15v. Most microcontrollers not capable of generating these voltages. So, to connect a microcontroller serial port to a true RS-232 device, you need to convert the TTL voltages of 0 and +5 into voltages between about -10 volts and +10 volts.

MAX232 is the chip that makes this work for you. It runs on a single chip supply (+5 volts), contains double charge pump voltage doubler and a +10v to -10v voltage inverter and requires a few external capacitors. There are some versions of this chip. The voltages output are used to generate the RS-232 compliant signals of two serial ports on the same physical package.

9 pin D-SUB male connector layout
9 pin D-SUB male connector
at the computer

at the device like a cellular phone
According to 10 reports in our database (7 positive and 3 negative) this pinout should be correct.

Is this pinout
This page contain parts under Copyright © 2000-2015 by pinouts.ru team.
No portion of this webpage may be reproduced in any form without providing visible HTML link to Pinouts.ru . Webmaster permission required in any other cases.
Efforts have been made to ensure this page is correct, but it is the responsibility of the user to verify the data is correct for their application.