GPIB Handshake Lines
The following table summarizes the GPIB handshake lines.
| Line | Description |
| NRFD (not ready for data) |
Listening device is ready/not ready to receive a message byte. Also used by the Talker to signal high-speed GPIB transfers. |
| NDAC (not data accepted) |
Listening device has/has not accepted a message byte. |
| DAV (data valid) |
Talking device indicates signals on data lines are stable (valid) data. |