Ceyear 1465 Series, Programming Manual

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2 Remote Control
2.3 I/O library
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Application
Instrument drive program (functional body)
Interactive developer
interface
Program developer
interface
Subprogram interface I/O interface (VISA)
Figure 2.12 Instrument Driver Structure Model
The detailed description is given as follows:
1) Functional body. It is the main functional part of the instrument driver and can be understood as the
framework program of the instrument driver.
。
2) Interactive developer interface. For user's convenience, a graphical interactive developer interface
is generally provided in the application development environment that supports the development of
the instrument driver. For example, the function panel in Labwindows/CVI is an interactive
developer interface. In the function panel, each parameter of the instrument driver function is
represented by a graphical control.
3) Program developer interface. It is a software interface for recalling of the instrument driver function
by the application, such as the dynamic link library file .dll of the instrument driver of the Windows
system.
4) I/O interface. It is used to complete the actual communication between the instrument driver and the
instrument. The special bus I/O software can be used, such as GPIB and RS-232; the general
standard I/O software across multiple buses can also be used, such as VISA I/O
。
5) Subroutine interface. It is a software interface for the instrument driver to access other support
libraries including database and FFT function. When the instrument driver needs to recall other
software modules, operating systems, program code libraries and analysis function libraries to
complete its task, the subprogram interface will be used.
2.3.2 Installation and configuration of I/O library
With the development of the test field application from the traditional instrument to the virtual instrument,
the instrument driver has experienced different development processes in order to solve the instrument
interchangeability and test program reusability of the automatic test system. Currently, the IVI
(Interchangeable Virtual Instruments) driver is popularly applied. Based on the IVI specification, a new
instrument programming interface is defined, the class driver and VPP architecture are inserted onto the
VISA so that the test application is completely independent of the instrument hardware, and unique
instrument simulation, range detection and status buffer functions are added, which improves the system
operation efficiency and truly achieves the instrument interchange.
IVI driver is divided into two types: IVI-C and IVI-COM. IVI-COM is based on Microsoft Component