Can I start a new 180 day period?

[SerendipitousNomads]

I need some Schengen visa assistance and I can't find anything regarding my situation in any searches elsewhere so hopefully someone here might be able to help me out...

I am Australian and arrived in the Schengen zone and commenced a Tourist Schengen Visa 90/180 day period.

I researched and found out that Portugal allowed me to extend my Schengen visa and stay an extra 90 days after the initial 90 days, provided I only use this visa for Portugal and not other Schengen member states. (Type C Visitor visa).
During this period, I travelled to Morocco through Spain and returned to Portugal without any issues with Spanish immigration.

My extension Type C Visa is soon to expire.  It will also be 180 days since my initial visa was commenced.
Would it be possible to start a new Tourist Schengen Visa 90/180 day period?

I wish to visit the Netherlands to see family for a period of one month before leaving to go back to Australia.

Does anyone have experience starting a new 180 day period whilst already in the schengen zone? Do you have to take your passport to an immigration authority to be stamped for a new period and if so, where do you go?

Or to start a new period, do you have to exit and re-enter the schengen zone?

Or, am I not entitled to start a new 180 day period until I have been outside the EU for 3 months?

Thanks in advance!

[danisara]

The "visa" that you have from Portugal, is it really a "visa", or is it a "residence permit"? I am afraid, the 90/180 rule still applies here. The period does not start and end on any specific date, it is rather a moving time frame. Search this forum, there are many posts about how the 90/180 rule works around here.