Pic18f4550

The Pic 18f4550 is a 16 bit in/out + 4 digital USB connected micro controller

I was wondering a Pic18f4550 costs about 6 dollar is there active development on it ?
>price > [www.ebay.com]
>schematic > [www.circuitvalley.com]

I was reading this [reprap.org] aperantly a main problem is there is no linux c++ interface
I do not know if reprap is only for linux, or also works on windows *

Aperantly it can be programmed from visual studio
see [www.waitingforfriday.com]


*) If the main goal is to do reprap on linux, thats no problem, but then i wonder is there a specific build used by rep rap ?


Reason to ask these questions i'm starting to learn the programming language C and wondered for some kind of test case to work on.

RepRap isn't Linux-only, but many developers use Linux. Because there you get all the free development tools and there you have the chance to enhance these tools. And most Linux tools work on Windows and the Mac, too, but not vice-versa.

Regarding this PIC: Unless this one is better than an ATmega in some aspect or another, I see no reason to develop for it. What can this chip do what an ATmega can't?

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Well it might bring the cost down, the chip you mention requires a reasonable board, and it costs about 30 or 40 dollar ?
I might be wrong here, so maybe you have cheap source for it. (do you have url ? )
For the rest i dont think its better or worse, from what i read about it may have less (but still enough) I/O ports.
I've seen solderings of the pic18f even without a board i think its more basic.

Thanks for the linux explanation, i'm in luxery that i have visual studio.
Sometimes its cool other times its dramatic (try creating an android app on visual studio, but its good in windows mobile).
Still one can create a app and post the code online, still the idea of sharing.
I have used linux in the past, but i'm not so deep into it. (i started with DOS 4.x)

An ATmega ist also in the $6 ballpark. Price for a single one: [www.reichelt.de]; Cheaper in larger, still modest quantities (100 ea.). Even ARM CPUs are said to be below $10, but no PDIP housing here.

That said, a processor with PDIP housing and a wider data bus would be very welcome. Unfoirtunately, I'm not aware of one. The need to calculate a lot of 32-bit integers with an 8-bit CPU ist the ATmega's bottleneck.

If you prefer these overfeatured IDEs, give Eclipse a try. Overwhelming.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Well eclipse brought me back to notepad++ type editors Edtira etc, (i used many).
I like an editor to be quick and small (Eclipse is huge) have code folding and to have code completion
Also visual studio is huge, but the other points are better then eclipse, the startup is reasonable.

If the price range is equal then having more I/O ports might be indeed better (i wonder if the PIC can directly stear the stepper mottors (with enough voltage). 8 to 32,.. thats just coding it's something i like to do.

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i wonder if the PIC can directly stear the stepper mottors

No. CPUs typically deliver some 20 to 40 mA, steppers require 1000 mA and up. You can add in MOSFETs (four per stepper), but then you have still no constant current circuitry, which is essential to achieve constant tourque over a range of speeds. There are attempts to make open source stepper drivers, readily available ones are cheaper and a lot easier to handle, though.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY