没有请求从* IDN返回？

大家好，我正在使用E5810B连接到GPIB总线。
连接的是不同的设备，例如HP，Anritsu，ifi。
将* IDN？-string发送到HP和Anritsu设备时，会返回正确的字符串，其中包含有关设备的全部信息。
问题是将* IDN？-string发送到ifi设备并返回“NO REQUEST”。
我现在知道的是IDN字符串格式错误，可能无法正确解析。
我检查了所有设置，手册说了什么，我不得不做。
我是新手使用GPIB，我找不到更好的发布地点。
有没有人有ifi设备的经验或有想法？
非常感谢你提前。
最好的祝福



     以下为原文

  Hello all,

I'm using a E5810B to connect to the GPIB-bus. Connected are different devices, such as HP, Anritsu, ifi.
When sending the *IDN?-string to the HP and Anritsu devices, the correct string comes back, containing the whole information about the device.
The problem is that sending the *IDN?-string to the ifi device a "NO REQUEST" is returned.  
What I now know is that the the IDN-string is badly formed and may not parse correctly.
I checked all the settings,what the manual said, I had to make.
I'm new to using GPIB, and I didn't find a better place to post this.
Does anyone have experience with ifi devices or has an idea?

Thank you very much in advance.

Best regards