A handler or prober driver coordinates a connected computer with the tester by using the driver entry point sequences to wait for a start-of-test (SOT) signal before beginning a test. Missing an SOT signal might cause the tester to wait indefinitely.

To ensure that a driver captures each SOT signal, the instrument communicating with the handler or prober must be armed for capturing the SOT signal before sending the end-of-test (EOT) signal. The handler or prober driver can capture the SOT signal if it occurs when the tester performs tasks during the tester index time or continue waiting until the SOT signal arrives.

Implement the following functionality in the driver entry points to ensure that the handler or prober driver captures all SOT signals:

Entry Point Functionality to Implement
Setup
  1. Open instrument sessions with which the handler or prober communicates.
  2. Configure the instrument with any armed triggers or monitoring ports for capturing the SOT signal.
  3. Query for any machine or lot information.
  4. Send any initialization routine to the handler or prober, such as load first wafer.
StartOfTest
  1. Determine whether the SOT signal was received.
  2. Continue monitoring for an end-of-lot (EOL) signal while waiting for the SOT signal. Check until the trigger arrives or the tester sends an EOL signal.
EndOfTest
  1. Reconfigure the instrument to capture the next SOT signal.
  2. Send the EOT signal, including any test results.
Cleanup
  1. Send a signal to stop the handler or prober.
  2. Close instrument sessions.