16 bit serial data communication

Hello,
I want to acquire data serially which is 16 bit.
Learning from the post http://forums.ni.com/t5/LabVIEW/16-bit-receive-over-rs-232/td-p/1214869/page/3
I was succeeded in joining the two eight bits. But the problem i am facing is that the two eight bits some time interchanges each other from MSB to LSB. The Block diagram Code is same as that from the above thread infact i have also plotted the data on Waveform Chart.
To simulate the behavior, i have created a program of 16 bit addition and sending the data as LSB and MSB on the serial port.
Here i am sending you the pics that may help you to identify the problem.
This is the first picture that shows the serial port properties, The graph, and the resulting string that contains LSB then
MSB and than the Conversion Result i.e 16 bit output.
This graph is exactly following the Conversion result
But when the LSB and MSB are interchanged this can we viewed clearly from this. Here the incremented result is reflected on MSB in place of LSB and has disturbed the whole program
The graphical representation of the error
In such Cases it is noted that the return count does not counts correctly as shown
To check whether the error is not at the transmission end,
I made another program in which I first send
1 2
3 4
5 6
7 8
9 10
And the same problem came here too. as shown below
Here you can see that I didn’t send 0 but 0 is here as
the first received data. Also the data is transmitted in five cycles but
received in six cycles also the return count is 1 again.
Waiting for reply
Thanks
Note:- I request you to please don't consider my another thread of Multichannel data receiving as same. They both are for different objective. Thanks

As i wrote that i have got the idea of 16 bit communication from the thread http://forums.ni.com/t5/LabVIEW/16-bit-receive-over-rs-232/td-p/1214869/page/3
The Code of this is also the same which is as under
Spoiler (Highlight to read)
Spoiler (Highlight to read)
The Data is transmitted as two serial bits and joined at the end. Wel can you give me a more clear idea of what could be the easy technique of specifying the start bit and stop bits.
Do you think that the data starts transmitting when some character is send to it. And then two bits and transmitted. Do you think this idea can solve the problem.

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Attachments:
test_serial.vi ‏167 KB

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5
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2
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Dear Sir!
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test41.vi ‏78 KB

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Attachments:
DIO_write_read DAQ from file.vi ‏17 KB

What does your file look like? The DAQmx write is expecting a single U32 value, not an array of I64.
Message Edited by vt92 on 09-16-2009 02:42 PM
"There is a God shaped vacuum in the heart of every man which cannot be filled by any created thing, but only by God, the Creator, made known through Jesus." - Blaise Pascal

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