Keithley 2661 Writing KULT Drivers free download

File name 2661 Writing KULT Drivers.pdf

technical note A G R E A T E R M E A S U R E O F C O N F I D E N C E Creating External Instrument Drivers for the Model 4200-SCS Introduction As the measurements performed on semiconductor devices grow increas- ingly complex, so does the demand for measurement automation. A typical test setup often involves several instruments performing sourcing, measurement, or auxiliary functions, all connected to a common commu- nications bus (typically GPIB) and controlled by a PC station. The Model 4200-SCS parameter analyzer eliminated the need for a dedicated PC. The Keithley Interactive Test Environment (KITE) allows the Model 4200-SCS to perform as both a parameter analyzer and an external instrument con- troller, making it the "command-and-control center" of the entire instru- ment rack. KITE software already supports several popular instruments, such as pulse generators, switch matrices, and C-V analyzers, through software control modules known as drivers. Occasionally, a user may need to control an instrument that's not sup- ported by a standard Keithley driver library. This technical note describes how to create custom instrument drivers. It assumes the reader is already familiar with the basic operation and software environment of the Model 4200-SCS, as well as with programming in C language. Overview In general, the Model 4200-SCS can control any external instrument connected to either the IEEE-488 (GPIB) bus or the RS-232 (serial) com- munication port, thanks to its flexible PC-based architecture. The GPIB protocol is currently the most widely used one. Figure 1 illustrates a multi-instrument system configuration. In the Model 4200-SCS, external equipment is controlled via the User Test Modules (UTMs), which are essentially C functions created and main- tained with the Keithley User Library Tool (KULT). Figure 2 illustrates the relationship between user modules, user libraries, UTMs, KITE, and KULT. From an operator's perspective, controlling an external instrument via a