I still with my fix so a problem. Here is a new fix. Please send comments.
A good test is tring to send from host to slave a DATA0 packet of 0x1e,
0x1f, 0xff, 0xff.

I would like to suggest now :

`DATA_RX_CHK_SE0:
begin
next_bitStuffError if (RxBits == `SE0)
begin
NextState_prRxBit end //RxBits == `SE0
else
begin
NextState_prRxBit if (RxBits == oldRXBits) //NRZI no change 1 /change 0
//if the current 'RxBits' are the same as the old 'RxBits', then
begin
next_RXSameBitCount //inc 'RXSameBitCount'
if (RXSameBitCount == `MAX_CONSEC_SAME_BITS)
//if 'RXSameBitCount' == 7 there has been a bit stuff error
next_bitStuffError //flag 'bitStuffError'
else //else no bit stuffing error
begin
next_RXBitCount if (RXBitCount != 4'h7) begin
next_processRxBitRdy //early indication of ready
end
next_RXByte //RZ bit end
end
else //else current 'RxBits' are
different from old 'RxBits'
begin
if (RXSameBitCount != `MAX_CONSEC_SAME_BITS)
//if this is not the RZ 0 bit after 6 consecutive RZ 1s, then
begin
next_RXBitCount if (RXBitCount != 4'h7) begin
next_processRxBitRdy //early indication of ready
end
next_RXByte //RZ bit end
//by PK
//old
//next_RXSameBitCount //old
//new
if (RXSameBitCount == `MAX_CONSEC_SAME_BITS)
next_RXSameBitCount else
next_RXSameBitCount //reset 'RXSameBitCount'
//new
//by PK
end
next_oldRXBits end
end