SparkFun Forums 

Where electronics enthusiasts find answers.

Have questions about a SparkFun product or board? This is the place to be.
By Martin Hodge
I would like to introduce a project I've been working on for the past year or so. The Propeller ASC. It is designed to be plug-in compatible with most existing Arduino shields. It adheres strictly to the mounting hole and connector layout of the Arduino, so it will fit existing enclosures as well. It is programmed in Paralax's SPIN language as well as native assembly (PASM). There is also 3rd party language support for many others incl ANSI C. It is not compatible with Arduino sketches (yet). The most unique feature of the Propeller is it's ability to generate simple video (VGA & Composite) using just a few resistors.

I am not affiliated with Parallax, I am making these myself. More info can be found here and here

If you don't know what the Propeller (P8X32A) uC is, I suggest skimming though this comparison/debate on the Parallax forum regarding the Propeller, ARM and XMOS. It does a good job at explaining how a chip with no interrupts and no hardware peripherals can be just as versatile and easy(er) to use.

By coyote20000
That's really nice. How many arduino shields work with 3.3v i/o though.
By Martin Hodge
coyote20000 wrote:That's really nice. How many arduino shields work with 3.3v i/o though.
Every shield I've tested so far:


A 3.3v signal can switch a 5v input since 3.3v is well above the VCC/2 at which most CMOS devices switch. The ASC has current limiting resistors to protect the Propeller's 3.3v inputs from over current when 5v is applied. The Propeller has internal protection diodes as well.
By mechG
Nice work, Martin. I can attest to how nice the Propeller is for building applications that need to manage lots of real-time processing. I have written apps for other, single-core chips using interrupt handlers, and it is so much easier with the Propeller because you can just dedicate a core (aka "cog") to each external device that requires real-time interaction.

I, too, am not affilated with Parallax -- just a happy consumer.
By minerva
Looks really good, Martin.

Just wondering... do you have any plans to release the schematics and board layout for this board openly?

One of the reasons I'm asking is that I need an Eagle library for the MCP3208 in a SOIC package... and if I could just grab your board file I could just use that part, without having to make it from scratch myself :D