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ericball
03-20-2009, 07:27 PM
Is there any limit on PLLA frequency when using the video generator, or will it work all the way up to 128MHz?
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cgracey
03-20-2009, 09:48 PM
128MHz is no problem for the video generator.

Feeding it data that fast·is the harder part.

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Chip Gracey
Parallax, Inc.

Cluso99
03-20-2009, 11:00 PM
Chip: I am presuming by your answer, we can run the prop up to 128MHz.
If so, is it ok to use 8MHz xtal and PLLx16 or do we need to use a 16MHz xtal and PLLx8? Is there anything else we should be aware of if using these speeds?

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· Single Board Computer·using the TriBladeProp board (ZiCog Z80 Emulator) (http://forums.parallax.com/showthread.php?p=790917)
· Prop Tools under Development or Completed (Index) (http://forums.parallax.com/showthread.php?p=753439)
· Emulators (Micros eg Altair, and Terminals eg VT100) - index (http://forums.parallax.com/showthread.php?p=778427)
· Search the Propeller forums (via Google) (http://search.parallax.com/search?site=parallax&client=parallax&output=xml_no_dtd&proxystylesheet=parallax&proxycustom=<HOME/>&ie=&oe=&lr=)

My cruising website is: ·www.bluemagic.biz (http://www.bluemagic.biz)·· MultiBladeProp is: www.bluemagic.biz/cluso.htm (http://www.bluemagic.biz/cluso.htm)

Mike Green
03-20-2009, 11:10 PM
Chip is referring to the video generator and cog counters only. There is a separate PLL for this use and it and the counters can run much faster than the chip as a whole. You can run the Propeller's system clock at 128MHz if you're willing to refrigerate the chip. See the graph in section 10.2 of the Propeller datasheet.

Cluso99
03-21-2009, 12:18 AM
Thanks Mike. I haven't played with the video generator or counters, so I thought I must have missed something.

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Links to other interesting threads:

· Home of the MultiBladeProps: TriBladeProp (http://forums.parallax.com/showthread.php?p=786418), SixBladeProp (http://forums.parallax.com/showthread.php?p=780033), website (Multiple propeller pcbs) (http://bluemagic.biz/cluso.htm)
· Single Board Computer·using the TriBladeProp board (ZiCog Z80 Emulator) (http://forums.parallax.com/showthread.php?p=790917)
· Prop Tools under Development or Completed (Index) (http://forums.parallax.com/showthread.php?p=753439)
· Emulators (Micros eg Altair, and Terminals eg VT100) - index (http://forums.parallax.com/showthread.php?p=778427)
· Search the Propeller forums (via Google) (http://search.parallax.com/search?site=parallax&client=parallax&output=xml_no_dtd&proxystylesheet=parallax&proxycustom=<HOME/>&ie=&oe=&lr=)

My cruising website is: ·www.bluemagic.biz (http://www.bluemagic.biz)·· MultiBladeProp is: www.bluemagic.biz/cluso.htm (http://www.bluemagic.biz/cluso.htm)