4 ms·

Pin RS232 Pinout Explained

• h2odragon 4y ago
  see also: https://allpinouts.org/pinouts/connectors/serial/rs232-eia-232-serial-25-pin/ https://allpinouts.org/pinouts/connectors/serial/rs232-eia-2... There were once devices that demanded all the nasty "secondary" lines be implemented.
• jaclaz 4y ago
  Truism of the week: >An RS232 pinout 9 pin cable features nine pins
  • h2odragon 4y ago
    But often not 9 actual cables; it was very common to find 8 wire cables that left RI floating.
    • jaclaz 4y ago
      Sure, just like the 25 pin connector in PC's was used with less than 25 wires cables, leaving most of the pins unconnected: https://allpinouts.org/pinouts/connectors/serial/pc-serial-25-pin/ https://allpinouts.org/pinouts/connectors/serial/pc-serial-2... still a 25 pin connector has twentyfive pins and a 9 pin one has nine pins. The same (DB25 or DB9) connector has been in use in countless devices with even less wires, null-modem cables had only 7: https://www.firewall.cx/networking-topics/cabling-utp-fibre/121-network-serial-cable.html https://www.firewall.cx/networking-topics/cabling-utp-fibre/... And if the cable/connection was monodirectional, even less, I seem to remember repairing a connector of a cable going to a serial printer having only 4 wires (or were they 5?) on a DB25 connector.