EIA232 Pin Description Index

Click on the desired pin to move to its description. Use "Back" on your browser to return here.

Note that these pin assignments are from the DTE side of the connection!

The most commonly used signals are shown in bold.

Shell - Shield
Pin 1 - Shield

Pin 2 - Transmitted Data
Pin 3 - Received Data
Pin 4 - Request to Send
Pin 5 - Clear to Send
Pin 6 - DCE Ready
Pin 7 - Signal Ground
Pin 8 - Received Line Signal Detect
Pin 9 - (reserved for testing)
Pin 10 - (reserved for testing)
Pin 11 - (unassigned)
Pin 12 - Secondary Received Line Signal Detect
Pin 13 - Secondary Clear to Send
Pin 14 - Secondary Transmitted Data
Pin 15 - Transmitter Signal Timing (DCE source)
Pin 16 - Secondary Received Data
Pin 17 - Receiver Signal Timing (DCE source)
Pin 18 - Local Loopback
Pin 19 - Secondary Request to Send
Pin 20 - DTE Ready
Pin 21 - Remote Loopback
Pin 22 - Ring Indicator
Pin 23 - Data Signal Rate Selector
Pin 24 - Transmitter Signal Timing (DTE source)
Pin 25 - Test Mode

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