USB-RS232 Converter Time-Out and Malfunctions

[ɸ6]

Hello Helpful People,

I am using a DYNEX usb-rs232 cable (prolific 2303chip) on windows 7 64bit and the evaluation of labview2011.  I am trying to do a basic task of connecting a tektronix tds210 scope to the computers usb port. 

I  have set up the drivers through NI Visa and MAX shows COM3 is working properly.  The VISA test panel shows

Read Operation
Error
VISA:  (Hex 0xBFFF0015) Timeout expired before operation completed

I have tried two different NI certified drivers for this scope and neither give me accessability to the scope. 

Thanks for your help in advance.

[Dennis_Knutson]

Verify the scope's com settings match what is being set in the initialize function and verify you have the correct type of serial cable - null modem or straight through.

[ɸ6]

Scopes setting match the settings shown in MAX, except the scope has the additional setting of EOL String which I have set to CR/LF as suggested by another message thread.

1.I dont have a multimeter in front of me, is there another way to test if this is a null or straight through cable?

2,  Should this be plug in play with the NI certified drivers, even with the adapter cable correctly setup or is there more to program?

Thank you

[Dennis_Knutson]

Doubt that there's such a basic bug in a driver this old. Could be though. You said you set the scope to to CR/LF. You can't do that with VISA so check what the driver is using for a single character. You could also double check with a terminal emulation program such as Hyperterminal.

No, you really a meter to check the wiring.

[ɸ6]

I agree this should be simple for old equipment.  Maybe I am too young.

The usb-serial cable obviously has one end USB, so checking Null/Straight seems difficult??? 

The serial end of the usb/serial adapter is male, the scope also has a male port.  I pulled a cord off another instrument that is female on both ends just to make the connection.  Maybe this was the problem from the start.  So the intermediate cable needs to be straight or null?

[Dennis_Knutson]

The intermediate cable needs to be what the manual says it should be. I have not used the scope in a long time and I do not remember what it is supposed to be.

[ɸ6]

I only see this

Full talk/listen modes

Control of all modes, settings and measurements.

Baud Rate up to 19,200.

9-Pin, DTE.

Thanks Dennis

[Dennis_Knutson]

The computer is also a DTE so you would need a null modem cable.

[ɸ6]

You mean a null cable between the scope and adapter?

Can the serial-usb adapter be null or straight, or does the chip inside take care of this??

I owe you 5 million dollars, thanks

[Dennis_Knutson]

Yes, between the scope and adapter. The adapter emulates a built-in serial port so it would function as a DTE.