Advantech PCL-832, Руководство пользователя

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Chapter 4 Programming 27
Microsoft C drivers and Turbo C drivers
The driver routines supplied with your PCL-832 were written for use
with Microsoft C and Turbo C. The functions covered by the
Microsoft C library are divided into system functions, preparatory
functions, motion functions and utility functions. The next two
sections describe the use of these functions.
The third section describes the Turbo C low-level drivers. These
drivers were written in Turbo C, and although only the basic functions
have been supplied, they should provide an adequate backbone for
your application. The source code is also supplied, which you can use
and customize as needed.
However, if you do not have a basic understanding of the concepts of
how the PCL-832 operates, the explanations/instructions given may
not make a lot of sense. It is advisable to read chapters 3 and 5 before
you go any further.
Special Procedures
When you use the Microsoft C libraries, the following is important:
1) The function main() is already used by the driver. Use
usermain() instead
2) The 8253 counter 0 (the IRQ generator in the PC) is used by the
driver, and the original value is modified for driver
purposes. DO NOT modify this register's value.
3) On the software diskette, there are three parameter files that are
used by the driver. Copy these files to the program directory
otherwise the driver will not work. The next section gives a brief
description of the parameter files.
4) When using the driver, reference is made to an incremental
coordinate system and an absolute coordinate system. When you
operate in the absolute coordinate system, references are made to
three fixed axis. In the incremental system, any position change
commands will occur relative to the current position of the
motors.
5) The libraries require a numeric co-processor to be present.