NI GPIB-140A总线扩展器 GPIB总线扩展器 - GPIB-140A可将GPIB系统的线缆延长一千米，而不会影响GPIB的完整性，也无需修改软件。该配件使用缓冲传输技术，数据传输速率高达1.1 Mb/s (IEEE 488.1)或2.8 Mb/s (HS488)。GPIB-140A还可以将GPIB系统中GPIB设备的最大数量从15个增加到26个。
模块从现场处理器接收电源，以运行其自身的5伏逻辑。外部
输入设备需要24VDC电源。
发光二极管
单个LED（逻辑侧），通过模块顶部的透明部分可见，
指示每个输入的开/关状态。现场和背板通电时，PWR LED亮起存在。
主机接口NI GPIB-140A
该模块的智能处理由总线接口单元或
系统。这包括配置输入默认值和故障报告等功能。这个
模块有16位（两个字节）的离散输入数据。需要一个总线接口单元来
将此输入数据提供给主机和/或本地处理器。
The module receives power from the Field Processor to run its own 5–volt logic. An external
24VDC supply is needed to power the input devices.
LEDs
Individual LEDs (logic side), visible through the transparent portion of the module top,
indicate the on/off status of each input. The PWR LED is on when field and backplane power
are present.
Host Interface
Intelligent processing for this module is performed by the Bus Interface Unit or elsewhere in
the system. This includes configuring features such as input defaults and fault reporting. The
module has 16 bits (two bytes) of discrete input data. A Bus Interface Unit is required to
provide this input data to the host and/or local processor.
