描述
模块化编程思想的应用:我们可以把正反自锁互锁转程序封装成为一个模块，正反转点动封装成为一个模块，在PLC程序中我们可以重复调用该模块，不但减少编程量，而且减少内存占用量,有利于大型PLC程序的编制。
NATIONAL INSTRUMENTS AT-GPIB DAQ ISA BOARD IEEE-488.2
National Instruments AT-MIO-16E-10 ISA Card 184309R-01
National Instruments GPIB-PCIII Interface Card 180250
NATIONAL INSTRUMENTS GPIB-130 BUS EXTENDER
National Instruments: 181830E-01 AT-GPIB/TNT Card
National Instruments GPIB X2 4.1 Meter Cable 763061-03
National Instruments: 183663C-01 AT-GPIB/TNT Card
National instrument PCI-GPIB interface card 183617E-01
NATIONAL INSTRUMENTS. GPIB-PCII
NATIONAL INSTRUMENTS AT-GPIB/TNT + 2Channel 488.2
