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Question on H1H2

Hi All,

I have a fundamental problem regarding the operation of 
H1 and H2 especially when positive or negative stuffing 

in receving frame N
H1[1]H2[1] : 0110_00_10_0000_1010 (default 522)

in receving frame N + 1 (positive stuff opportunity)
H1[1]H2[1] : 0110_00_00_1010_0000

what should i expect in frame N + 2 ?
(1) H1[1]H2[1] : 0110_00_10_0000_1011
(2) H1[1]H2[1] : 1001_00_10_0000_1011 <- inverting NDF
(3) others

would frame N + 3 H1[1]H2[1] be 0110_00_10_0000_1011 ?

For the receive side, the wan phy should be able to
process arbitrary H1H2 pointer.   
Should new pointer value only be updated when NDF 
is inverted?  

Does this mean the very very first frame H1H2 should 
actually be H1[1]H2[1] : 1001_00_10_0000_1010 and the 
subsequent frames be H1[1]H2[1] : 0110_00_10_0000_1010?

If this is the case, the wan phy could actually miss 
the first NDF.  If the default H1H2 is also 522, then
this would not be a problem.  What happen if the frame
pointer value is anything other than 522?  Can the phy
re-sync itself to the correct pointer?

Have a good weekend.

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