Keithley KTTI-RS232 – Communication and Digital I/O

• Provides instruments with an accessory card slot with an RS-232 interface
• Provides six independently configurable digital input/output lines that can be used to control external digital circuitry
• Digital I/O port is a standard female DB-9 connector
• Can generate output trigger pulses and detect input trigger pulses
• I/O connector: DB-9, female connector

The KTTI-RS232 Communication and Digital I/O Accessory provides instruments with an accessory card slot with an RS-232 interface.

The card provides six independently configurable digital input/output lines that can be used to control external digital circuitry, for example, a handler that is used to perform binning operations. The digital I/O port is a standard female DB-9 connector. You can also use these lines for triggering. The instrument can generate output trigger pulses and detect input trigger pulses.

The RS-232 serial port can be connected to the serial port of a controller using a straight-through RS232 cable terminated with DB-9 connectors. Do not use a null modem cable.

The serial port uses the transmit (TXD), receive (RXD), and signal ground (GND) lines of the RS232 standard. The figure below shows the rear panel connector for the RS232 interface. The table below shows the pinouts for the connector.

The baud rate is the rate at which the instrument and the attached device communicate. The factory-selected

baud rate is 9600, but you can choose from any of these available rates.

• 115200
• 57600
• 38400
• 19200
• 9600
• 4800
• 2400
• 1200
• 600
• 300

When you choose a baud rate, make sure the attached device can support the selected rate. The instrument

and the attached device must be configured for the same baud rate.

1. Press the MENU key.

2. Select Communication.

3. Set the Baud Rate option.

4. Set Flow Control.

The KTTI-RS232 digital I/O port provides six independently configurable digital input/output lines.

You can use these lines for digital control by writing a bit pattern to the digital I/O lines. Digital control is used for applications such as providing binning codes to a component handler. Digital control uses the state of the line to determine the action to take.

You can also use these lines for triggering by using the transition of the line state to initiate an action. The instrument can generate output trigger pulses and detect input trigger pulses. Triggering is used for applications such as synchronizing the operations of a measurement instrument with the operations of other instruments.

You cannot configure or directly control the digital I/O lines from the front panel. To configure and control any of the six digital input/output lines, you need to send commands to the KTTI-RS232 over a remote interface. You can use either the SCPI or TSP command set.

See Remote communications interfaces in the instrument reference manual for information about setting up a remote interface and choosing a command set.

The digital I/O port uses a standard female DB-9 connector, located on the rear panel of the KTTI-RS232. You can connect to the KTTI-RS232 digital I/O using a standard male DB-9 connector. The port provides a connection point to each of the six digital I/O lines and other connections.