Slow read of first character from VISA TCP/IP socket

[GeoffA]

Hi John,

We have used the real RS232 (COM1) on PCs to connect to ESP300/301 controllers for years without any serious problems. However, we have only done bench tests with the ESP302 RS232 (COM1) interface and made sure that the interface was initialized using the attached VI code. We also explicitly disable the software limits in the ESP302 for our application, although for us this prevents errors, not timeouts.

I hope this helps.

Regards,

Geoff.

[JÞB]

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@JohnHWhite wrote:

I am trying to control the ESP302 via RS232 but through a RS232 to USB adaptor as well as the adaptor supplied by Newport (Previously we used the ESP301 via USB). Ethernet is fine but via RS232/USB all I get is timeouts 

I am guessing you connected directly to a RS232 port on a PC?

The settings are as per Newport's example code for the ESP301

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Funny thing about USB to RS-232 adapters.... not all of them support CTR / RTS! and of course you need 5 lines in the RS-232 cable itself to use hardware handshakes not just GND TX RX.  Those are the most common oversights that can bite you. I'm not sure what settings are available in the device itself (often handshake < none | Term Char | Hardware>  on the DTE has to be set to match your DCE port)

If any of those acronyms are not familiar to you. Google RS-232