Reply by Peter Jakacki●September 21, 20062006-09-21
Isaac Bosompem wrote:
> The chip looks nice to play with but @ $129 USD for a devkit it would
> put a hole in my wallet. That SPIN language looks cool too! I am just
> delving thru the datasheet to see how everything goes together.
My local distributor has the DIP40 + EEPROM + CRYSTAL for $24.20AUD. If
you look at the demo board schematics you will see that is all you need
other than a 3.3V supply and a bit of board to mount it all on. Use two
pencell batteries and skip the regulator if you like. There is nothing
that the demo board has that you can't do yourself with bits from the
junk-box. The serial port can be a simple 2 transistor affair.
In fact I think the absolute bare minimum would be just the chip and a
3V supply as you can boot this off the serial port and run it off it's
internal oscillator.
*Peter*
Reply by Isaac Bosompem●September 21, 20062006-09-21
Peter Jakacki wrote:
> I haven't heard anyone talking about the Propeller since earlier in the
> year when it had just been released so I'd like to share my impression
> of it with anyone who is interested. BTW, I have been heavily into
> LPC21xx ARM chips the last year or so and this is something completely
> different.
>
> I received a Parallax Propeller eval board last week and I have been
> hooked on it since. At the moment I have my board outputting 128 chars x
> 64 lines VGA text in color, outputting an independent TV text display in
> color, reading from an electret microphone directly (only Rs & Cs) and
> digitizing using internal sigma-delta into a buffer with delay and echo
> and spitting that out at the same time through another RC network
> straight into the monitors speakers. Meanwhile a PS/2 keyboard and a
> serial coms port as well as I2C is operating.
>
> There are no glitches or hiccups, it just runs as smooth as, all this
> without external h/w support, I am impressed.
>
> Sure, it doesn't have a 512K byte Flash, it loads it's software through
> the serial port or an external I2C EEPROM into it's 32K of main RAM
> which sounds a bit limited, but look what it can do with it! The
> Propeller is comprised of eight 32-bit processors each with it's own 2K
> byte RAM connected to a central hub with the 32K of main RAM and 32K
> ROM. You can find out more at http://www.parallax.com/propeller/index.asp
>
> The price has just been halved by Parallax to promote volume use.
>
> Parallax have an active forum running but has anyone else had experience
> with this chip?
>
> *Peter*
The chip looks nice to play with but @ $129 USD for a devkit it would
put a hole in my wallet. That SPIN language looks cool too! I am just
delving thru the datasheet to see how everything goes together.
-Isaac
Reply by Steve at fivetrees●September 20, 20062006-09-20
"Peter Jakacki" <peterjak@tpg.com.au> wrote in message
news:450e4d11$1@dnews.tpgi.com.au...
>I haven't heard anyone talking about the Propeller since earlier in the
>year when it had just been released so I'd like to share my impression of
>it with anyone who is interested. BTW, I have been heavily into LPC21xx ARM
>chips the last year or so and this is something completely different.
>
> I received a Parallax Propeller eval board last week and I have been
> hooked on it since. At the moment I have my board outputting 128 chars x
> 64 lines VGA text in color, outputting an independent TV text display in
> color, reading from an electret microphone directly (only Rs & Cs) and
> digitizing using internal sigma-delta into a buffer with delay and echo
> and spitting that out at the same time through another RC network straight
> into the monitors speakers. Meanwhile a PS/2 keyboard and a serial coms
> port as well as I2C is operating.
>
> There are no glitches or hiccups, it just runs as smooth as, all this
> without external h/w support, I am impressed.
You have me intrigued. I have a project coming up that requires generating
several HF signals count-locked to a 1kHz IRIG timing code, and this looks
like a very interesting contender. Even if I decide to do it some other way,
it's still a cute device. I shall read more. Thanks.
Steve
http://www.fivetrees.com
Reply by David Ashley●September 19, 20062006-09-19
Peter Jakacki wrote:
> I have just uploaded some of my recent screen shots of the Propeller
> running VGA and TV displays.
>
> http://www.pbjtech.com/cpu/propeller/
>
> *Peter*
Pictures look interesting. The graphics consist of lines in some cases.
Lines require memory. But this thing doesn't have enough memory
for the display. So how are the lines displayed?
I can imagine a system where you just have a display list, say a
list of lines to draw and a color for each. Then you have 2 small
strip buffers, and you clip all the lines to one of the buffers and
draw what would appear in that strip. Meanwhile you're displaying
the other. What a headache.
Every step of the game you're going to be butting up against the
hard 32K byte memory limit.
-Dave
--
David Ashley http://www.xdr.com/dash
Embedded linux, device drivers, system architecture
Reply by Peter Jakacki●September 18, 20062006-09-18
Reply by Peter Jakacki●September 18, 20062006-09-18
David Ashley wrote:
> On the website it shows $25.00 for each chip, does that mean the price
> is now $12.50?
When I purchased this last week the distributor charged me half price
because he said that Parallax had just cut the price. Both Parallax's
and his website still show the old price but I guess the website
designer is a little slow.
>
> I'm wondering what the target application would be for this. 32K isn't a
> lot to work with for software, you'd have to struggle to fit an mp3 player
> in that even if it's possible. mpeg-2 or -4 decoding...
Hey, I can't see how I would do MP3 with the current chip either, but
then again take a look at the Hydra at http://www.xgamestation.com/ to
see what is being done with the Propeller, WOW!
>
> I can see an approach where this device is a versatile helper processor
> for the main cpu, which would have much more memory. The parallax
> would be like handling the innermost loop in stuff. It would do its
> functions
> through bit banging in software say. DAC done with timer interrupt
> outputting
> samples at a steady rate. Video...I don't see how the chip could output a
> stable video signal fast enough without additional support circuitry. A low
> resolution 640x480 vga display requires a dot clock in the 25 mhz realm.
Yes, I can see this processor will "sometimes" be better off as a slave
processor, it could replace what would have required an FPGA. Part of
the power of the Propeller lies in the 2 dedicated counters and video
registers per cog. It is possible to synthesis frequencies up to 128MHz
as each counter has it's own PLL. Some guy even stuck a bit of wire out
of one of the ports as a Q&D 49MHz RF transmitter for a toy.
There are no interrupts because you can devote a whole processor to a
function but the DAC function is implemented by using a counter (1 of
16) in delta modulation mode outputting at 40MHz so that only a simple
RC filter is needed. The chip runs at 80MHz off a 5MHz crystal.
The same goes for ADC, although you could do sigma-delta with the cpu it
is much easier to configure a counter for this.
The video registers can generate multiple 1024x768 VGA and/or TV video
but it is up to a COG or two to process the frame data at this rate as
there is very little RAM (at present).
>
> If you think of it as a low end programmable hardware type device then it
> sort of makes sense, your software turnaround times will be much faster
> than with FPGA development. Bandwidth in and out of the device will probably
> be a limiting factor. The 32K RAM size...that's too small for the cpu
> horsepower
> there is it seems to me.
The 32K does seem a little small when compared to the memory sizes of
many 32-bit embedded micros now. However this sounds just like the PC
programmer who looks at these whiz-bang 32-bit micros and who used to
100's of megabytes on the PC. You and I know you don't need that kind of
memory but it sure is hard for the poor guy to get his head around it.
>
> I just can't see a killer APP for it at its current price. If the price
> were $5
> possibilities could open up.
This chip is very new and I guess when they are selling volume they will
be able to amortize their costs and also shift to a smaller process as
their chips are 0.35um at present. Just think what it would mean if they
shifted even to 0.18um.
>
> It sounds like a cool toy though. Alternative to the CEL architecture
> and it's
> available now. Programming both would be similiar I expect.
Remember that this chip must be one of the very few that is even
available in a 40-pin DIP pack which is what is required for those
"great idea! let's try it out" moments. They also have QFP44 and QFN44
packs.
Don't expect to use C to program this chip but the Parallax have
developed their own language called "Spin". You can program a cog in
assembler or Spin, here is a sample of Spin.
_____________________
PUB Toggle(Pin, Delay, Count)
{{Toggle Pin, Count times with Delay clock cycles in between.}}
dira[Pin]~~ 'Set I/O pin to output direction
repeat Count
!outa[Pin] ' Toggle I/O Pin
waitcnt(Delay + cnt) ' Wait for Delay cycles
_____________________
Using the supplied Propeller tool (IDE) for software development is
extremely simple, there is practically no learning curve. A tap of the
F10 will see your code compiled and downloaded into the chip within the
blink of an eye, well that's certainly how I found it.
I can't wait for when they do come out with Propeller II but until then
there are plenty of applications that I am planning with the current chip.
*Peter*
Reply by David Ashley●September 18, 20062006-09-18
Peter Jakacki wrote:
> Sure, it doesn't have a 512K byte Flash, it loads it's software through
> the serial port or an external I2C EEPROM into it's 32K of main RAM
> which sounds a bit limited, but look what it can do with it! The
> Propeller is comprised of eight 32-bit processors each with it's own 2K
> byte RAM connected to a central hub with the 32K of main RAM and 32K
> ROM. You can find out more at http://www.parallax.com/propeller/index.asp
>
> The price has just been halved by Parallax to promote volume use.
On the website it shows $25.00 for each chip, does that mean the price
is now $12.50?
I'm wondering what the target application would be for this. 32K isn't a
lot to work with for software, you'd have to struggle to fit an mp3 player
in that even if it's possible. mpeg-2 or -4 decoding...
I can see an approach where this device is a versatile helper processor
for the main cpu, which would have much more memory. The parallax
would be like handling the innermost loop in stuff. It would do its
functions
through bit banging in software say. DAC done with timer interrupt
outputting
samples at a steady rate. Video...I don't see how the chip could output a
stable video signal fast enough without additional support circuitry. A low
resolution 640x480 vga display requires a dot clock in the 25 mhz realm.
If you think of it as a low end programmable hardware type device then it
sort of makes sense, your software turnaround times will be much faster
than with FPGA development. Bandwidth in and out of the device will probably
be a limiting factor. The 32K RAM size...that's too small for the cpu
horsepower
there is it seems to me.
I just can't see a killer APP for it at its current price. If the price
were $5
possibilities could open up.
It sounds like a cool toy though. Alternative to the CEL architecture
and it's
available now. Programming both would be similiar I expect.
-Dave
--
David Ashley http://www.xdr.com/dash
Embedded linux, device drivers, system architecture
Reply by Jim Granville●September 18, 20062006-09-18
Peter Jakacki wrote:
> I haven't heard anyone talking about the Propeller since earlier in the
> year when it had just been released so I'd like to share my impression
> of it with anyone who is interested. BTW, I have been heavily into
> LPC21xx ARM chips the last year or so and this is something completely
> different.
>
> I received a Parallax Propeller eval board last week and I have been
> hooked on it since. At the moment I have my board outputting 128 chars x
> 64 lines VGA text in color, outputting an independent TV text display in
> color, reading from an electret microphone directly (only Rs & Cs) and
> digitizing using internal sigma-delta into a buffer with delay and echo
> and spitting that out at the same time through another RC network
> straight into the monitors speakers. Meanwhile a PS/2 keyboard and a
> serial coms port as well as I2C is operating.
>
> There are no glitches or hiccups, it just runs as smooth as, all this
> without external h/w support, I am impressed.
>
> Sure, it doesn't have a 512K byte Flash, it loads it's software through
> the serial port or an external I2C EEPROM into it's 32K of main RAM
> which sounds a bit limited, but look what it can do with it! The
> Propeller is comprised of eight 32-bit processors each with it's own 2K
> byte RAM connected to a central hub with the 32K of main RAM and 32K
> ROM. You can find out more at http://www.parallax.com/propeller/index.asp
>
> The price has just been halved by Parallax to promote volume use.
>
> Parallax have an active forum running but has anyone else had experience
> with this chip?
Hi Peter,
Yes, the device is something different. Nice to see something fresh,
and I can see it would suit a class-room very well.
(I also like the new Zilog ZNEO, as class-friendly, but it is not as
radical as the nifty propellor)
-jg
Reply by Peter Jakacki●September 18, 20062006-09-18
I haven't heard anyone talking about the Propeller since earlier in the
year when it had just been released so I'd like to share my impression
of it with anyone who is interested. BTW, I have been heavily into
LPC21xx ARM chips the last year or so and this is something completely
different.
I received a Parallax Propeller eval board last week and I have been
hooked on it since. At the moment I have my board outputting 128 chars x
64 lines VGA text in color, outputting an independent TV text display in
color, reading from an electret microphone directly (only Rs & Cs) and
digitizing using internal sigma-delta into a buffer with delay and echo
and spitting that out at the same time through another RC network
straight into the monitors speakers. Meanwhile a PS/2 keyboard and a
serial coms port as well as I2C is operating.
There are no glitches or hiccups, it just runs as smooth as, all this
without external h/w support, I am impressed.
Sure, it doesn't have a 512K byte Flash, it loads it's software through
the serial port or an external I2C EEPROM into it's 32K of main RAM
which sounds a bit limited, but look what it can do with it! The
Propeller is comprised of eight 32-bit processors each with it's own 2K
byte RAM connected to a central hub with the 32K of main RAM and 32K
ROM. You can find out more at http://www.parallax.com/propeller/index.asp
The price has just been halved by Parallax to promote volume use.
Parallax have an active forum running but has anyone else had experience
with this chip?
*Peter*