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Posts: 2

Timeout errors on 2nd read

Win NT, serial port COM1. I inherited this project because it doesn't work as is, so I'm completely in the dark.

When using CWSerial1 in VB6, I am getting -1002 (or 30301) timeout errors. This usually occurs when attempting to read data a second time. In Excel, I can't read even once. I'm even not sure my COM1 is configured properly -- using the hyperterminal test, I do not get double characters, using the paperclip loop on a cable I seem to be able only to send. But, I can't find anything else to change on the config. I have updated cwinstr.ocx to the most recent version. We have several instruments which use GPIB and the application works fine for them, but the same application toggled for serial and this instrument does not.

Any help is appreciated. I hope it is something obvious.
Posts: 21

Re: Timeout errors on 2nd read

Try hyperterminal test (with and without paperclip) on different com ports and see what you get. Make sure you dont have any other application open that uses serial ports. While doing hyperterminal test, make sure you select none for flow control and parity while doing port settings. Try changing ports and see what happens. You might have a bad com port and this hyperterminal test will tell us that. I know you have taken hyperterminal test but i want to know in little detail about the results and what happens when you try other ports.
Posts: 2

Re: Timeout errors on 2nd read

Ketan, thanks for your help.

I've tried both com1 and com2, with and without the paperclip, and get the same results -- no echo. Even though "Echo typed characters locally" was checked.

I hope this give you some idea as to what is happening.