How many REAL video HZ?

Discuss emulation of the Nintendo Entertainment System and Famicom.

Moderator: Moderators

Post Reply
User avatar
Anes
Posts: 702
Joined: Tue Dec 21, 2004 8:35 pm
Location: Mendoza, Argentina

How many REAL video HZ?

Post by Anes »

Hi, i know as stated in electronic image that NTSC is not equal exactly to 60hz and that PAL and Dendy neither.
So i wish to know the exactly HZ NTSC, PAL and Deny runs.

Im just curious.
ANes
User avatar
Quietust
Posts: 1920
Joined: Sun Sep 19, 2004 10:59 pm
Contact:

Re: How many REAL video HZ?

Post by Quietust »

As stated on the wiki (perhaps not in the most obvious location), the NTSC NES outputs video at 60.09881Hz (1789772.7272727 divided by 29780.5) and the PAL NES (and presumably also the Dendy) outputs video at 50.00698Hz (1662607 divided by 33247.5).
Quietust, QMT Productions
P.S. If you don't get this note, let me know and I'll write you another.
User avatar
Anes
Posts: 702
Joined: Tue Dec 21, 2004 8:35 pm
Location: Mendoza, Argentina

Re: How many REAL video HZ?

Post by Anes »

Oh what a full didnt know about that page/link.
I should googled and navigate better. :oops:

Thanks for the info Quietust.
ANes
ap9
Posts: 43
Joined: Sat Jun 01, 2013 11:55 am
Location: Maine, U.S.A.
Contact:

Re: How many REAL video HZ?

Post by ap9 »

For NTSC, 60.09881 is only the average when rendering is on.
It's actually somewhere between 60.0984776 and 60.0991502 because the colorburst clock is part of the timing; there are times when rendering is off, which can stop the colorburst clock from changing state.

The program can control the refresh rate, so the exact time for a given frame requires counting the cycles.
User avatar
Anes
Posts: 702
Joined: Tue Dec 21, 2004 8:35 pm
Location: Mendoza, Argentina

Re: How many REAL video HZ?

Post by Anes »

ap9 wrote: Fri Apr 01, 2022 3:21 pm For NTSC, 60.09881 is only the average when rendering is on.
Ok thanks!!
ANes
Post Reply