My "eeZeeProp" Propeller Breakout Board

shimniok

I've restocked on eeZee Propeller boards available on Tindie. You can now get them with Arctic edition as well as original OSHPark Purple

What is it? A better Propeller breakout board for breadboarding. Compare to:

• Propstick USB? Mine costs less.
• Sparkfun Breakout? Mine's less expensive and mine includes the crystal
• Quickstart? Mine is breadboard friendly
• Propeller Mini? Mine breaks out all the GPIO pins

What can it do? Anything a Propeller can do. An earlier rev of this board runs RoboTurkey, a 3-servo animatronic Thanksgiving Turkey that plays back recordings of my little girl saying things like "I'm stuffed" or "Pass the gravy". Rev 0.2 rang a bell every time someone visited my blog during the 2011 holidays.

Rev 0.5 Features

• Budget friendly, breadboard friendly
• 5MHz Crystal, 32k EEPROM, filtering caps, reset circuit, power indicator LED
• Flexible power options: FTDI, external 5V, external 3.3V, etc.
• Onboard 800mA 3.3V regulator that can also power your projects out of the 3.3V pin.
• Flexible programming options: use Prop Plug or FTDI
• The pins are spaced at 0.800", all Prop IO pins exposed plus reset.
• BOE is configurable with a solder jumper.
• Open source, make your own if you want!

Documentation: here

rogloh

Looks very nice. Just wondering though... doesn't the FTDI breakout for the DTR signal that is directly connected to the reset pin in the schematic for this board get shorted to ground if you were to ever press the reset button with it attached? It would be okay if it was an open collector output driving the reset, but I am not sure it is with FTDI so wouldn't a signal diode be needed here to protect these outputs from a direct short to ground? I guess a reasonable current answer might just be: "don't do that".

I know some people also capacitively couple these DTR signals to reset (eg. protoboard) but I've never really liked that approach myself. Hate to see those RC spikes on the reset lines. In the past I've tend to use diodes on any driven reset signal outputs to pull down the CPU reset inputs (in conjunction with a pullup resistor - as you already have), or some type of transistor circuit that behaves like an O/C output.

shimniok

rogloh wrote: »

Looks very nice. Just wondering though... doesn't the FTDI breakout for the DTR signal that is directly connected to the reset pin in the schematic for this board get shorted to ground if you were to ever press the reset button with it attached? It would be okay if it was an open collector output driving the reset, but I am not sure it is with FTDI so wouldn't a signal diode be needed here to protect these outputs from a direct short to ground? I guess a reasonable current answer might just be: "don't do that".

Good question. I'll dig into this further. "Don't do that" will probably be the answer for now. Or at least "don't do that for very long"

I know some people also capacitively couple these DTR signals to reset (eg. protoboard) but I've never really liked that approach myself.

I've had issues getting that to work reliably in some cases. I do this on breadboard AVRs.

Hate to see those RC spikes on the reset lines. In the past I've tend to use diodes on any driven reset signal outputs to pull down the CPU reset inputs (in conjunction with a pullup resistor - as you already have), or some type of transistor circuit that behaves like an O/C output.

That's probably a better practice. Moreover I ran across this forum post: http://goo.gl/mELOL

There's an app note from Atmel that suggests diode, a couple caps, pullups, etc... Of course Propeller is a different animal. I'll go back and take a closer look at the Prop Plug and various Parallax Prop boards.

Thanks again!

Michael

Bill Henning

Looks very nice - congratulations!

shimniok

Found this circuit diagram linked from another forum post. http://www.parallax.com/Portals/0/Downloads/docs/prod/prop/32212-32812-PropellerProtoBoard-v1.3.pdf

Basically a 0.01uF to pass transients to an NPN with pulldown on the base, that, when briefly activated by negative transition on DTR, makes the npn conduct to pulls down reset through a pullup resistor.

I'll give it a whirl. It should work... as I always say...

rogloh

Yep I have that same protoboard which also uses an FTDI chip to drive the Reset via DTR and associated transistor. I found it certainly works fine with the PropTool software resetting the board reliably each time. Adding it to your board would make it safe to drive the reset line either externally or via your pushbutton without shorting anything. The other forum post your dug up is certainly useful for background information on this stuff.

Good stuff.
Roger.

shimniok

I put it up on Tindie as a fundraiser to see if there's any interest in making more of these.

https://tindie.com/shops/bot_thoughts/eezee-propeller/

Thanks,
Michael

prof_braino

Looks cool and perfect for breadboard prototyping. Only thing is the price, for a buck more (actually a buck fifty less, today) I can get a quickstart.

How many would have to be ordered before the price was significantly lower than a quickstart?

jazzed

tinde.com is a cool idea So, 24 boards at $24 each is the minimum quantity?

shimniok

Thanks for the input!

I needed a breadboard friendly Propeller that was much cheaper than the PropStick and without the onboard FTDI. It's $28 shipped in the US if the fundraiser goes through.

The Quickstart looks like a really nice board with a lot of extras that's great for learning the Propeller. It's not what I need but if money is really tight and a few bucks matters more than the form factor, I'd suggest this route.

Likewise, another great board at a very good price is the Schmartboard Propeller board. I like mine. However, for some time, I've been using my own eeZee Prop boards instead

To try to compete with Parallax's Quickstart price/volume/margin is unrealistic for me to say the least.

But if you want a breadboard friendly Propeller designed and assembled by a maker for other makers here in the US (boards are made here too), well... here it is.

If not, no worries!

thanks,
Michael

shimniok

I've got over 20 pre-orders, so I'm definitely making a batch.

Any last minute pre-orders? It's the last day of the Tindie Fundraiser! - https://tindie.com/shops/bot_thoughts/eezee-propeller/

shimniok

Anyone else interested before I order parts? Click the "eeZee Prop" link in my signature and click the "notify me when it's available" button if you want one.

I've ordered the boards for the initial Tindie Fundraiser and expect those back in a couple weeks. I'll order more of those and extra parts if there's additional demand.

Thanks, all!

lanternfish

Hi shimniok

I ahve done the Tindie 'thing' as you requested. I certainly will be interested in 2 - 3 eeZeeProp's.

Nice job by the way.:thumb:

shimniok

Thanks I appreciate it! I'll be sure to make some extras for ya.

rogloh

Hey shimniok, probably too late notice now but I am interested in a couple as well. I tried adding my email to your "notify me when its available" page but got a "Forbidden (403)" response CSRF verification failed whatever that is. Running IE8 with cookies enabled so dunno what happened there.

Did you end up changing the reset circuit a bit since the original in this board spin? I'll still take 'em if you haven't.

Roger.

shimniok

rogloh wrote: »

Hey shimniok, probably too late notice now but I am interested in a couple as well. I tried adding my email to your "notify me when its available" page but got a "Forbidden (403)" response CSRF verification failed whatever that is. Running IE8 with cookies enabled so dunno what happened there.

Huh, weird. Did you get it working? I got a notification that someone just added themselves to the notify list.

Did you end up changing the reset circuit a bit since the original in this board spin? I'll still take 'em if you haven't.

Yes, I am now using the prop plug type reset circuit after testing it on my rev 0.2 boards (pictured at the top).

I also changed the supply circuit a little. There's two diodes. One on the FTDI 5V line, one on the VIN pin. you can bypass the latter so that, with the FTDI hooked up, you get 5V (well VUSB) out of the VIN pin.

Lastly, there's now a solder jumper to configure BOE.

Michael

rogloh

Huh, weird. Did you get it working? I got a notification that someone just added themselves to the notify list.

Not yesterday but just now I retried on a Mac running Safari and it let me, so I should be on your list now Michael. :thumb:

Regards,
Roger.

shimniok

Cool, thanks

I just ordered parts last night for the first batch plus extra to cover the folks on the waiting list.

shimniok

Check it out! I guess I am onto something https://www.sparkfun.com/products/11525

I don't even have my frigging boards back from the fab house yet and they're off to market Ah well, that's what happens when you are a big company with capital and all the manufacturing goodies at your disposal.

The designer said that he arrived at his design independently. Neat. I'm encouraged and glad SFE is doing a version.

Anyway, my boards will be in early next week to fulfill the fundraiser support/orders. I'm working on the test jig (bed o nails) in the meantime.

I should have some in stock for general sale in other several weeks after I get through the fundraiser adventure.

Cluso99

shimniok: You have done a nice job and I wish you success. The more prop boards out there the better

However, your board is not unique. There are plenty of others around including my 1"x1" CpuBlade (search the forum)

shimniok

@Cluso99 -- nice job!!

WBA Consulting

Shimniok, I have a hard time believing that your design was not seen during the development of this. While Cluso is correct in regards to several other small layouts, the similarities of the "unique" features of yours and theirs is uncanny. The $35 price tag is hard to swallow compared to yours. I didn't verify the pinout, but how close is it too yours?

Cluso99

Their pinout is different and pcb size is longer. But the 4 & 6 pin connectors at the end, even though the pinout is different, is somewhat unique. So I would agree their design is different, but certainly some features seem uncanny if they didn't see your design. And $35 is high.

lanternfish

Had to race off to Oz last week and only just saw the notification today from Tindie that the boards were back in stock. Only to find that they are sold out again.
They were such a good price. Sparkfun equivalent is tad too expensive so I guess I will have to pop over to Cluso's site and get 2 or 3 of his CPUBlades.

shimniok

I'll have more in stock in a few weeks. Actually there's 1 in stock right now.

If you want the older Rev 0.2 boards let me know. Only difference is the Rev 0.2 doesn't have the transistor reset for the FTDI DTR input.

shimniok

I'm posting up the Rev 0.2 boards cheap ($16) in case anyone wants 'em.

Only difference between them and the latest Rev is they don't have the transistor reset circuit and BOE is permanently grounded.

The side pins are populated so I have to box 'em so shipping is a bit higher.

Thanks,
Michael

rogloh

Hi shimniok,

I am expecting a couple of rev0.3 eeZeeProp boards to arrive anytime this week, is there a chance you can update your schematic pdfs in the rev0.3 documentation area below? They still seem to show the prior rev0.2 variant for some reason.

https://code.google.com/p/bot-thoughts-eezee/source/browse/#svn%2Ftags%2FeeZee_Prop_0.3

Thanks,
rogloh

shimniok

Whoops. I'll get that updated in the next few days

rogloh

Great. The boards just arrived today - they are looking really good and are the perfect size to work with on one of these

http://www.freetronics.com/collections/protoshields/products/protoshield-basic

Now hoping to get busy with some soldering this weekend.

shimniok

Great! Would like to see / hear what you build.

shimniok

eeZee Propellers on sale $26 at the Bot Thoughts Store through the end of March.