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rickman <gnuarm@gmail.com> writes:
> Weird, your posts all show up in my reader as replies to your own
> messages rather than replies to my posts. The trimming made it hard for
> me to figure out just what we were talking about with the odd
> connections in my reader.
Sorry. I'm assuming your reader is threading via the "References" field?
It looks like my posting software is preserving that.
> > The chip has a lower level bit stream engine which the higher level CPU
> > ("cog") is feeding. Well, a pair of cogs. Each cog has local memory
> > and then a really expensive path through a central arbiter ("hub"). It
> > fills its image of the scanlines from the shared memory, then has to
> > feed it via waitvid into the lower level. Note that it's bit stream
> > engine *per cog*, so you also have to worry about their sync.
> I can't picture the processing with this description. I don't know
> about the higher level and lower level CPUs you describe. Are you
> saying there is some sort of dedicated hardware in each CPU for video?
> Or is this separate from the CPUs? Why a *pair* of COGs? I assume a
> COG is the Propeller term for a CPU?
Yes, each cog has its own PLL and "video" bit stream engine (quotes because
they claim it can be used for any sort of analog stream in general). They
needed to use a pair of cogs (CPU's) because of the time it takes to pull
from screen memory as conceived by the ANSI emulation and generate the
scan lines to represent the font plus underline plus cursor. So the idea
is one is doing all that while the other is painting scan lines. Double
buffering, basically.
> Not 100%? What does that mean? Magic? I guess this is the magic smoke
> you want to keep from getting out of the chip?
Yes, there is no formal/deterministic way to lock the PLL's of the two
cogs. Everybody uses the sample code Parallax provided, and it has
definitely been shown that their "lock" can be skewed.
> I still don't know enough about the architecture to know what this
> means. I don't care if the CPUs are not coordinated closely. If you
> have a video engine providing the clock timing, why would the CPU timing
> matter?
They have *two* video engines. Each is generated from its own PLL, so
the first global clock is a crystal oscillator.
> > Anyway, you should buy one and check it out. I'd be curious to hear
> > if (1) you also observe the same video quality, and (2) if you think it's
> > the waitvid mechanism, more the PLL->SVGA generation, or the sync issues
> > of the paired video generators. They even supply the schematic, FWIW.
> I appreciate your enthusiasm, but I have my own goals and projects. I
> am currently oriented towards absurdly low power levels in digital
> designs and am working on a design that will require no explicit power
> source, it will scavenge power from the environment. I don't think a
> Propeller is suitable for such a task is it?
Darn, because I'm pretty sure you are much better equipped to drill
down into this than I. :-> But, no way, a Propeller is definitely a
traditional CPU for your purposes.
Andy Valencia
Home page: http://www.vsta.org/andy/
To contact me: http://www.vsta.org/contact/andy.html
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Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-13 06:37 +0000
Re: Parallax Propeller MK <mk@nospam.co.uk> - 2013-01-13 10:26 +0000
Re: Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-13 12:22 +0000
Re: Parallax Propeller Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-01-13 07:24 -0600
Re: Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-13 13:55 +0000
Re: Parallax Propeller mhx@iae.nl (Marcel Hendrix) - 2013-01-13 17:13 +0200
Re: Parallax Propeller Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-01-16 06:23 -0600
Re: Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-16 15:01 +0000
Re: Parallax Propeller Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-01-16 09:12 -0600
Re: Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-16 15:36 +0000
Re: Parallax Propeller Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-01-16 10:59 -0600
Re: Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-16 23:38 +0000
Re: Parallax Propeller Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-01-17 04:04 -0600
Re: Parallax Propeller Mark Wills <forthfreak@gmail.com> - 2013-01-17 04:52 -0800
Re: Parallax Propeller Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-01-24 22:48 -0800
Re: Parallax Propeller Mark Wills <forthfreak@gmail.com> - 2013-01-24 23:10 -0800
Re: Parallax Propeller Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-01-28 17:42 -0800
Re: Parallax Propeller "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-02-05 06:05 -0500
Re: Parallax Propeller Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-02-05 08:41 -0600
Re: Parallax Propeller Paul Rubin <no.email@nospam.invalid> - 2013-02-05 10:21 -0800
Re: Parallax Propeller Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-05 21:37 +0100
Re: Parallax Propeller "Elizabeth D. Rather" <erather@forth.com> - 2013-02-05 10:44 -1000
Re: Parallax Propeller Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-02-05 15:52 -0600
Re: Parallax Propeller Paul Rubin <no.email@nospam.invalid> - 2013-02-06 00:29 -0800
Re: Parallax Propeller Paul Rubin <no.email@nospam.invalid> - 2013-02-06 00:31 -0800
Re: Parallax Propeller Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-06 19:46 +0100
Re: Parallax Propeller Paul Rubin <no.email@nospam.invalid> - 2013-02-09 00:11 -0800
Re: Parallax Propeller anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-02-09 10:25 +0000
Re: Parallax Propeller Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-06 18:26 -0800
Re: Parallax Propeller Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-05 15:07 -0800
Re: Parallax Propeller Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-05 15:49 -0800
Re: Parallax Propeller "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-02-05 06:04 -0500
Re: Parallax Propeller Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-05 15:21 -0800
Re: Parallax Propeller rickman <gnuarm@gmail.com> - 2013-01-16 18:09 -0500
Re: Parallax Propeller Ben Bradley <ben_u_bradley@etcmail.com> - 2013-01-18 21:07 -0500
Re: Parallax Propeller "Paul E. Bennett" <Paul_E.Bennett@topmail.co.uk> - 2013-01-19 10:06 +0000
Re: Parallax Propeller Arlet Ottens <usenet+5@c-scape.nl> - 2013-01-19 13:04 +0100
Re: Parallax Propeller "A. K." <akk@nospam.org> - 2013-01-19 13:22 +0100
Re: Parallax Propeller Bernd Paysan <bernd.paysan@gmx.de> - 2013-01-19 13:38 +0100
Re: Parallax Propeller David Brown <david.brown@removethis.hesbynett.no> - 2013-01-19 17:12 +0100
Re: Parallax Propeller albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-01-19 16:45 +0000
Re: Parallax Propeller David Brown <david.brown@removethis.hesbynett.no> - 2013-01-20 17:49 +0100
Re: Parallax Propeller upsidedown@downunder.com - 2013-01-19 20:54 +0200
Re: Parallax Propeller Paul Rubin <no.email@nospam.invalid> - 2013-01-19 11:04 -0800
Re: Parallax Propeller upsidedown@downunder.com - 2013-01-19 23:05 +0200
Re: Parallax Propeller Mark Wills <markrobertwills@yahoo.co.uk> - 2013-01-20 01:05 -0800
Re: Parallax Propeller Arlet Ottens <usenet+5@c-scape.nl> - 2013-01-20 12:11 +0100
Re: Parallax Propeller upsidedown@downunder.com - 2013-01-20 13:53 +0200
Re: Parallax Propeller upsidedown@downunder.com - 2013-01-20 13:26 +0200
Re: Parallax Propeller Les Cargill <lcargill99@comcast.com> - 2013-01-19 14:23 -0600
Re: Parallax Propeller Les Cargill <lcargill99@comcast.com> - 2013-01-19 14:18 -0600
Re: Parallax Propeller David Brown <david.brown@removethis.hesbynett.no> - 2013-01-20 20:32 +0100
Re: Parallax Propeller Les Cargill <lcargill99@comcast.com> - 2013-01-20 18:08 -0600
Re: Parallax Propeller Walter Banks <walter@bytecraft.com> - 2013-01-20 17:12 -0500
Re: Parallax Propeller Mel Wilson <mwilson@the-wire.com> - 2013-01-20 19:19 -0500
Re: Parallax Propeller Walter Banks <walter@bytecraft.com> - 2013-01-20 21:12 -0500
Re: Parallax Propeller David Brown <david@westcontrol.removethisbit.com> - 2013-01-21 09:01 +0100
Re: Parallax Propeller Walter Banks <walter@bytecraft.com> - 2013-01-21 21:11 -0500
Re: Parallax Propeller upsidedown@downunder.com - 2013-01-22 09:39 +0200
Re: Parallax Propeller Mel Wilson <mwilson@the-wire.com> - 2013-01-22 10:14 -0500
Re: Parallax Propeller Waldek Hebisch <hebisch@math.uni.wroc.pl> - 2013-01-20 02:03 +0000
Re: Parallax Propeller George Neuner <gneuner2@comcast.net> - 2013-01-19 12:29 -0500
Re: Parallax Propeller rickman <gnuarm@gmail.com> - 2013-01-23 12:29 -0500
Re: Parallax Propeller Mark Wills <markrobertwills@yahoo.co.uk> - 2013-01-24 14:03 -0800
Re: Parallax Propeller Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-01-24 22:55 -0800
Re: Parallax Propeller Mark Wills <forthfreak@gmail.com> - 2013-01-24 23:03 -0800
Re: Parallax Propeller Coos Haak <chforth@hccnet.nl> - 2013-01-25 20:02 +0100
Re: Parallax Propeller Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-01-28 17:13 -0800
Re: Parallax Propeller David Brown <david@westcontrol.removethisbit.com> - 2013-01-29 09:15 +0100
Re: Parallax Propeller Anders.Montonen@kapsi.spam.stop.fi.invalid - 2013-01-30 12:19 +0000
Re: Parallax Propeller David Brown <david.brown@removethis.hesbynett.no> - 2013-01-30 21:18 +0100
Re: Parallax Propeller Mark Wills <forthfreak@gmail.com> - 2013-01-30 22:57 -0800
Re: Parallax Propeller Alex McDonald <blog@rivadpm.com> - 2013-01-31 10:38 -0800
Re: Parallax Propeller Mark Wills <forthfreak@gmail.com> - 2013-01-31 12:34 -0800
Re: Parallax Propeller Paul Rubin <no.email@nospam.invalid> - 2013-01-19 10:42 -0800
Re: Parallax Propeller bob@bob.com - 2013-01-19 19:56 -0600
Re: Parallax Propeller rickman <gnuarm@gmail.com> - 2013-01-23 12:40 -0500
Re: Parallax Propeller None <vandys@vsta.org> - 2013-01-24 23:26 +0000
Re: Parallax Propeller Walter Banks <walter@bytecraft.com> - 2013-01-25 11:49 -0500
Re: Parallax Propeller rickman <gnuarm@gmail.com> - 2013-01-25 09:25 -0500
Re: Parallax Propeller None <vandys@vsta.org> - 2013-01-25 21:57 +0000
Re: Parallax Propeller rickman <gnuarm@gmail.com> - 2013-01-26 18:07 -0500
Re: Parallax Propeller Mark Wills <markrobertwills@yahoo.co.uk> - 2013-01-27 00:50 -0800
Re: Parallax Propeller Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-01-27 03:30 -0600
Re: Parallax Propeller Dombo <dombo@disposable.invalid> - 2013-01-27 12:58 +0100
Re: Parallax Propeller rickman <gnuarm@gmail.com> - 2013-01-28 21:38 -0500
Re: Parallax Propeller None <vandys@vsta.org> - 2013-01-27 03:09 +0000
Re: Parallax Propeller rickman <gnuarm@gmail.com> - 2013-01-28 21:51 -0500
Re: Parallax Propeller None <vandys@vsta.org> - 2013-01-30 02:10 +0000
Re: Parallax Propeller rickman <gnuarm@gmail.com> - 2013-01-30 18:32 -0500
Re: Parallax Propeller David Schultz <abuse@127.0.0.1> - 2013-01-20 11:21 -0600
Re: Parallax Propeller albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-01-13 16:24 +0000
Re: Parallax Propeller David Brown <david@westcontrol.removethisbit.com> - 2013-01-14 10:51 +0100
Re: Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-16 06:06 +0000
Re: Parallax Propeller David Brown <david@westcontrol.removethisbit.com> - 2013-01-16 13:43 +0100
Re: Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-16 15:27 +0000
Re: Parallax Propeller Rafael Deliano <rafael_deliano@arcor.de> - 2013-01-15 21:10 +0100
Re: Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-16 06:26 +0000
Re: Parallax Propeller gavino_himself <visploveslisp@gmail.com> - 2013-01-22 06:26 -0800
Re: Parallax Propeller Peter Jakacki <peterjakacki@gmail.com> - 2013-01-13 12:44 +0000
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