cellphone cable and connector wiring scheme
9 pin D-SUB male connector to the computer
18 pin Samsung SGH-600 cell phone special connector to the cellular phone
- This scheme is some kind of RS-232 Converter.
- Almost all digital devices USED require TTL or CMOS logic levels. That’s why the first step when trying to connect the device to RS-232 port is transformation of RS-232 levels ack into 0 and 5 Volts. This is done by RS-232 Level Converters, like a Max 232.