Best route to develop on the new P2, which hardware do I go for?
Coley
Posts: 1,108
I'm looking to get back into P2 development after a long absence and have a few ideas that I am bouncing around with Baggers.
What is the best board to purchase with the latest silicon?
Is it the P2 ES Evaluation Board or is there something else?
Are there any members of the forum developing boards already?
Thanks,
Coley
What is the best board to purchase with the latest silicon?
Is it the P2 ES Evaluation Board or is there something else?
Are there any members of the forum developing boards already?
Thanks,
Coley
Comments
and the Accessory Kit to go with it.
It would be great to have you two working on Propeller stuff again!
Peter is working on one, (and almost ready).
https://forums.parallax.com/discussion/168645/p2d2-an-open-hardware-reference-design-for-the-p2-cpu
https://forums.parallax.com/discussion/170695/p2d2-with-p2-revb-taking-orders/p1
In addition to the Eval board that @Publison linked, you might want the Hyper memory breakout for games/video development...
https://www.parallax.com/product/64004-es
Top tip is to plug the HyperMemory into the left-hand side of the RevB Eval board (P0 to P15), as the latest version of the eval has those pins as matched length traces to meet the HyperRam/Flash specs and hopefully improve throughput by a hair.
You could connect up to three of the HyperRam/Flash modules to the Eval, keeping the top Eval edge connector for programming and perhaps the HDMI or AV breakout from the accessory kit.
Thanks
What are the main differences between Rev A and Rev B silicon?
Are they listed somewhere?
Thanks @Publison , I'll take a closer look at this.
Here is some info on the change from A to B:
https://docs.google.com/document/d/1gn6oaT5Ib7CytvlZHacmrSbVBJsD9t_-kmvjd7nUR6o/edit
https://forums.parallax.com/discussion/171196/pnut-spin2-latest-version-v34g#latest
Rev A silicon has few in the wild, and is EOL. Focus on Rev B (Rev B+) as that is what you will be able to get on newly ordered boards.
Rev B and Rev B+ are the same verilog, rev B+ is the volume production parts with a metal change to slightly lower ADC crosstalk.
It's missing a lot of features that the newer silicon has and you'd need to use the tools that were made for it at the time. Everything has moved forward since then.
Maybe we should come up with a price for replacing the P2 on older Eval boards. It's a tedious process. I don't think we'd want to do too many, as it ties up our best assembly person. We'd have to charge $50, or so. Would you be interested in that?
Yes, of course. Grab an older fastspin compiler and make it into a permanent project or a wall or desk display.
But do realize we're collectively not going back to rev A. Your PLL isn't very good so video will be wobbly, there's some sign extension bugs in certain hardware, and addpins and certain pointer instructions won't work. So you'd need to get familiar with all of this and rewrite code every time.
Rev A were very limited engineering samples, and we need to get them out of circulation and out of our collective mindset and conversations. Keep moving forward.
That's something I would do with my Rev A board actually.
Hey @Coley!
Right now, it's the Eval Board, Peter has just about completed his P2D2 board, or roll your own with some loose chips.
The Eval is a great little package. Using the add on boards are easy. To me, that package is like the Demo Board was, only with modular reference circuits rather than everything baked into the board. If you do go that route, getting two accessory sets can make sense when you want to do the same task multiple times.
There's also the P2LAB dev board which the P2D2 plugs into as a module and then there's P2PAL that is a thin smd layer that goes onto the back of the P2D2 and supports HyperRAM, PSRAM, ESP32, and has a proper micro SD socket etc. But I'm holding off on this a bit until I get these orders out. I have enough distractions as they are.
You need the new chip. PM me with your details and we'll work it out.
I have the Eval board but it's revision A, that's why I wondered what the differences were.
In truth it's probably going to be ok for the short term plan we have, I need to look in more detail at the docs.
Is the streamer and/or Video affected by Rev B?
Are there any other differences between the PCB's? I seem to remember there being a few issues related to power?
You had to pick 1 or 2 for the first divider...
Also, it used a lot more power...
What are you going to code in, Coley? Personally, from a development point of view, I'd just get started with what you have, the differences aren't huge
They changed slightly between Rev.A and Rev.B.
I'd try to find a PNut from before Rev.B. It comes with some examples.
You can also try to find a FlexGui from then too.
Thanks Rayman
You're right, the Rev A will do for now, we can always progress to Rev B if need be.
As for what we will code in, looking at the tools so far there seems to be quite a lot of choice but if Baggers has anything to do with it it'll be mostly PASM2 ;-)
- New immediate modes for serialised data to match the equivalent read-fast modes.
- New immediate, read-fast and write-fast modes for varying DAC bit-depths.
- New write-fast modes and smartpin paths for ADC sampling direct to hubRAM - Scope mode.
- TMDS encoding for DVI/HDMI added to CMOD.
As a result, the mode number encodings have all been reorganised. Including moving bit-fields between D and S.
Wasn't there a digital I/O glitch with Rev.A when changing both out and dir at the same time (as with drvh, for example)?
If so, something to be aware of maybe...