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FTDI start bit

Hi!

 

I am connecting to FTDI USB to RS232 chip I downloaded the DLL and Labview driver and examples. But I could not get it working on a loop to a serial PC port, I connected to the Oscilloscope and I noticed it not sending the first bit.

 

How can I configure it to send a start bit (0 -binary).

 

Thanks 

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What driver? I've never seen this with the vcp driver.
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I used D2XX DLL and the D2XX function library. Also if you look at the example demo when confirure the interface there is not option to start bit. Thanks

 

from:

http://www.ftdichip.com/Support/SoftwareExamples/CodeExamples/LabVIEW.htm

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@cualquiera wrote:

Hi!

 

I am connecting to FTDI USB to RS232 chip I downloaded the DLL and Labview driver and examples. But I could not get it working on a loop to a serial PC port, I connected to the Oscilloscope and I noticed it not sending the first bit.

 

How can I configure it to send a start bit (0 -binary).

 

Thanks 


I really think you are going about it backwards.  Try starting with basic stuff instead of mucking with scoping the individual lines.  Does it show up as a COM port in Device Manager?  How about MAX?  Are you using the correct resource in your code?

 

Can you develop code to work on ANY serial port?  As far as LabVIEW is concerned, this is just another serial port.  If you don't know how to communicate through a serial port, you won't know how to communicate with the adapter.

 

Edit: Why not just use basic VISA serial to talk with it?  That way it is scalabe because your code will work with any COM port, not just the virtual one.

Bill
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@billko wrote:

@cualquiera wrote:

Hi!

 

I am connecting to FTDI USB to RS232 chip I downloaded the DLL and Labview driver and examples. But I could not get it working on a loop to a serial PC port, I connected to the Oscilloscope and I noticed it not sending the first bit.

 

How can I configure it to send a start bit (0 -binary).

 

Thanks 


I really think you are going about it backwards.  Try starting with basic stuff instead of mucking with scoping the individual lines.  Does it show up as a COM port in Device Manager?  How about MAX?  Are you using the correct resource in your code?

 

Can you develop code to work on ANY serial port?  As far as LabVIEW is concerned, this is just another serial port.  If you don't know how to communicate through a serial port, you won't know how to communicate with the adapter.

 

Edit: Why not just use basic VISA serial to talk with it?  That way it is scalabe because your code will work with any COM port, not just the virtual one.


mmmm... I think what I am doing cannot go any basic. this chip is a USB to a Serial, so I connect driver and use the example as it is (which to me look at any sinple USB communication) I had it connected to a PC and look at serial comunitation through niMAX (serial port) and I was getting wrong values (could not get it to work) so the most basic is look at the serial communications with the Osciloscope and I notice there is not start bit, then I also notice there is not the option to set the start bit (you need to notice this is the USB to Serial link)  Thanks

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Use the vcp driver if you want a serial port. Much simpler to use, in my opinion and more robust. That is really the basic option. If you have a problem with the d2xx driver, contact ftdi.
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Advantages of vcp:

Your code will work when a built-in com port is used.
Your code will work when a converter from another vendor is used.
Communication can be debugged with a common program such as putty, tera term, etc.
Instrument drivers from NI can be used unmodified.

Advantages of d2xx:
You fill in this section.
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