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someone please explain me the logic in this vb code

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techyfubky

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'Shift bit to the right
dim tempval, amount as long
Dim SendBuff(0 To 255) As Byte
tempval = amount
For index = 1 To 24
tempval = tempval / 2
Next index

SendBuff(6) = tempval And &HFF

tempval = amount
For index = 1 To 16
tempval = tempval / 2
Next index

SendBuff(7) = tempval And &HFF

tempval = amount
For index = 1 To 8
tempval = tempval / 2
Next index

SendBuff(8) = tempval And &HFF
SendBuff(9) = amount And &HFF



The above code splits the Long value "amount " into bytes some lsb in sendbuff(9)..
Please explain me how this happens.....!


Also the following code

' RecvBuff(3)=234, (RecvBuff(2)=1 the values in the bytes
amount = RecvBuff(3)
amount = amount + (RecvBuff(2) * 256)
amount = amount + (RecvBuff(1) * 65536) '256 * 256
amount = amount + (RecvBuff(0) * 16777216) '256 * 256 * 256
tbValue.Text = CStr(amount)


' obtained result is 490' I really dont get the idea behind this logic...
 

It is equivalent to

SendBuff(6 ) = (amount / 16777216) And &HFF
SendBuff(7 ) = (amount / 65536) And &HFF
SendBuff(8 ) = (amount / 256) And &HFF
SendBuff(9 ) = amount And &HFF
 

@AMK Thanks for your explanation.

Actual operation in which this code is a part of is in writing a numerical value into a block of size 16 byte.

I want to know how this manipulation affects in storing what value in which place..

Can someone show light on this issue please...!
 

This code is not affecting the order of bytes, but shifts it 6 places between Receive and send buffer.

i.e. RecvBuff(3) has the Least significant Byte which actually goes to SendBuff(9).
 

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