The Electronics Industry Association (EIA) has developed standards for data communication. EIA standards where originally marked with the prefix "RS". "RS" means that it is a recommended standard, but the standards are now generally indicated as "EIA" standards.
RS-232 was introduced in 1962. The standard evolved over the years and had the third revision in 1969 (RS-232C). The fourth revision was in 1987(RS-232D also known as EIA-232D).
RS-232 is identical to the standards CCITT V.24/V.28, X.20bis/X.21bis and ISO IS2110.
Connection
RJ45 norm B color | Function |
white/orange | 1 - out 1 |
orange | 2 - out 2 |
x | 3 – Txd |
blue | 4 – GND |
x | 5 - in 1 |
green | 6 - Rxd |
white/brown | 7 - +12V |
brown | 8 - |
Basic Serial 9600
- "Standard" RS-232, 9600Baud
- Type M1
Basic Serial 19200
- 19200Baud