P2P3?
rjo__
Posts: 2,114
I have been secreted away trying to fathom the inner workings of applescriptobjc radio buttons. I am planning to post my Prop2<-->Mac serial terminal in the near future.
My present complaint? I can no longer tell the difference between discussions about the P2 and the P3. I love them both but mixing them together is giving me a migraine.
Help!!!!!
My present complaint? I can no longer tell the difference between discussions about the P2 and the P3. I love them both but mixing them together is giving me a migraine.
Help!!!!!
Comments
Seriously, my rationale is this: The P2 is called the P8X32C, because it's 8 cores and 32 bits, 3rd rev.
The P3 will be a P8X64A or somesuch because it has 64 bit operands.
Engineering says 40/48/56 bits could be fine, but Marketing would not cope with anything less than 64 bits.
Of course, even 64 bits is somewhat elastic, and some 8 bit controllers with a few 16 bit opcodes, claim to be 16 bit.
The P2 already has some 64 bit operands and results, so it can claim to be somewhat 64 bit capable already.
Where 64 bit has practical use, is in intermediate value for scaling. Res = A * B / C
With 40bit, the COG instruction/register space could be 16 times larger, with 48bits it could be 256 times larger. Although I think with a 48bit instruction size, it would make sense to have S and D be 16bits each, and add 2 bits to the opcode field it would be cleaner. 64k instructions/registers ( 384KB (6 bytes per register) ) per cog would be pretty deluxe. HUB memory will need to be pretty darn large, probably something like 4MB at least.
As much as the thread seems to be bouncing all over and venturing further and further away from the P1, I wonder if there is any reason to call this new chip a Propeller at all. Is it really the next version of Propeller 1 or something mostly different?
Also as far as I can tell the P2 still looks like a P1 with an order of magnitude more speed and HUB RAM and a lot more pins.
Of course a ton of new features and instructions have been added but I think you can still ignore most of that and program it with a P1 mindset.
I'm sure Ken would like some stable status reports as well.
Ah, you are talking about opcode size.
Seems to me there will always be some waste.
If you default variable size to 32 bits, with some 64 bit double-size VAR, then Data nicely fills COG memory, but opcode=32 bit.
If you nudge that to 40 bits, because VAR data is still 32 bits, now COG memory storing opcodes is 100% used, but COG memory storing Data is only 32 bit, so wastes 20% -. (or do you add a Boolean Var space, like the 8051 has ?)
Or you can make it more Harvard like, with 40/48 bit opcode space and 32/64 bit data arrays, and now no memory is wasted, but you have lost self modifying code....or made it clumsier.
-Phil
Anyone familiar in programming P1 can switch to a P2 without having to start at Page 1 in the manual.
Most of the instructions that you would be used to in P1 are there in P2.
The opcodes might be different but the operation is the same.
You still only have 512 longs of COG ram (-12 regs) so nothing really different there.
The transition from P1 to P2 PASM is not as steep a learning curve as people may think.
Sure there are differences in the Peripheral stuff but the fundamental COG concept remains.
I have found the experience of coming from P1 to P2 quite painless.
From a "virtual P2 users" perspective, the "look and feel" of P1 is definitely present in P2.
P2 is definitely a PROPELLER
DONT PANIC people!
We are so close.
Ozpropdev
Others are now banging the drums for a kickstarter funded P3.
It's all getting more cloudy and Silicon Valley vaporwore like.
Personally I would like to see a real P2 along with a functional GCC compiler and library so the rest of us non-gurus could actually use it. Until then I'll stick with the Cortex M4 and Pic32.
I would be very hesitant to call the consistent updates on features and the debates contained within a "status update". If I handled my project reports in the same manner, I would be setting myself up for a clear path of demotion. The development and marketing of this chip is a crucial business avenue for Parallax and should be treated as such. Due to Parallax's effort to provide an "open" nature of this process, I would expect there would be an update every 2 weeks on key items of the development, foundry run timeline, key specs, FGPA testing progress, etc. Instead, the Update Blog has turned into a 3 year long monstrosity of a thread that is impossible to comprehend except by those on it daily as part of the process.
I looked back at the first post to get the start date and caught this comment while there:
Maybe I am venting because I feel the longevity of my beloved Propeller 1 could be put at risk depending on the outcome of the P2 timeline. Anyhow, here's my Propeller 2 Countdown Timer. I hope it's attainable.
I'm in camp with WBA, Phil, rod1963, et al. - P2 does seem a ways away from P1; if not in type, then certainly in scale. Regardless, it's a dream right now - we'll see what P2 is and how it fits in when there actually is a finished chip (or even a finished specification). In the meantime, I am more concerned about P1 and how all this might affect it.
??
P2 has already helped P1 significantly, it has helped seed the GCC development.
There comes a time in every project, when its time to shoot the engineers ship something.
and no I was on the engineering side, not marketing.
I did not say it was required, I said it seeded - clearly GCC is there now, and P2 is not.
The prospect of P2 galvanized action. Certainly a good thing for P1.
Only if Parallax go broke.
Salaries have to be covered, but they are not large external costs. Large external costs are what send companies broke.
P1 is a proven die, they can order more at very low risk, and almost no man-hour cost.
I really do not see this imagined connection between P2 design, and P1 future ?
There are other reasons, like products that simply don't sell as expected (or simply having no viable product at all).
Are P1 sales growing or shrinking? If P2 fails, after all this time and money, and P1 sales have been trending down anyway (in part thanks to inattention), what happens to Parallax? What if there is no P2 until, say, 2017?
It's really quite easy to see the potential connection - takes no trouble at all.