2600系列和2600A系列数字源表之间还存在着其他几个差异：

There are a few other differences of note between Series 2600 and Series 2600A instruments:

•双精度运算：2600系列数字源表采用单精度浮点运算，而2600A系列数字源表[1]则采用双精度浮点运算。注意，如果现有软件程序的编写容易受到四舍五入或截断误差的影响，那么这一点是非常重要的。典型后果包括：

• Double-precision math: Series 2600 instruments use single-precision floating point math. Series 2600A instruments use double-precision floating point math. This is important to note if the existing software programwas written in a way as to be susceptible to roundoff ortruncation error. Typical ramifications include:

 

– 条件环路退出行为不同。例如，假设将一个环路设置为当电压<1.0时退出。在双精度运算中，当测量值为0.999999990时环路仍将继续，但在单精度运算中，就将退出环路。

– Different exit behaviors for conditional loops. Forexample， assume a loop is programmed to exit when(voltage <1.0). A measured value of 0.999999990would continue looping in double-precision， but exit insingle-precision.

 

– 计算的参数值和数学值略有不同。其中包括内插值或推断值(如阈值电压)；数字微分或斜坡计算值(如跨导)；或者数字积分值(如通过对测量电流进行积分而计算出的电流)。

– Slightly different results for calculated parameters andmathematical values. This includes interpolated orextrapolated values (such as threshold voltage); valuesfrom numerical differential or slope calculations (such astransconductance); or numerically integrated values (suchas charge calculated by integrating measured current).

 

•reset()命令：同2600系列数字源表中发布的reset()命令相比，在2600A系列数字源表中发布的reset()命令更加全面。某些特性具有不同的默认状态。例如，现在数字I/O线路的默认触发模式是TRIG_BYPASS，允许直接读写至数字I/O线路。在中间件1.3.4版本或更早的版本，2600系列数字源表[2]的默认触发模式是TRIG_FALLING。在2600A系列数字源表的数字I/O线路发送和接收触发时，其模式必须明确设置为支持的硬件触发模式之一。

•reset() command: Issuing a reset() on the Series2600A is far more comprehensive than on Series 2600instruments. Some properties have different default states.For example， the default trigger mode for digital I/O linesis now TRIG_BYPASS， which permits direct read and writeto digital I/O lines. On firmware version 1.3.4 and earlier，the default mode for Series 2600 (non-A) instruments wasTRIG_FALLING. To send and receive triggers on the Series2600A digital I/O lines， the mode must be explicitly set forone of the supported hardware trigger modes.

 

• 更新工厂脚本[3]：在吉时利工厂脚本中创建的调用功能的任何软件程序都是后向兼容的。此外，用户可以访问所有工厂脚本的源代码，包括KI Pulse功能。为了利用2600A系列数字源表的新特性，许多工厂脚本功能是重新编写的，如触发模式。对需要为其自身应用编写类似功能和脚本的用户来说，这个源代码可以作为一个很好的例子。

• Updating of factory scripts: Any software programsthat call functions created in Keithley factory scripts arebackward compatible. Moreover， users can access the sourcecode for all factory scripts， including KI Pulse functions.Many of the factory script functions have been rewrittento utilize new features of Series 2600A instruments， suchas the trigger model. This source code can serve as anexcellent set of examples for users who need to writesimilar functions and scripts for their own applications.

 

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     要想了解有关2600A系列数字源表或者吉时利其他系列数字源表的更多信息，或者咨询全套直接可用的多通道测试系统的价格，请点击https://admin.acrobat.com/_a16893448/p81871518/，或者联系吉时利公司：全国免费电话800-810-1334手机用户请拨打440-650-1334。

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