Please, if anybody knows more about power off flag (POF), how & where & why to use during software or hardware reset, let me know more.
The POF is derivative dependent, typically it is set on power up (Vcc getting to 5V) you can manually reset it and then, on following resets test it.
Also nothing is mentioned in PDF files regarding SMOD1 7th bit (MSB) of PCON please let me know the same.
Which PDF files? The programmers guide and instruction set on page 2-11 in The Intel "bible" (see links for address) clearly states how it works

Erik