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EMX versus USBizi (memory concerns)


#1

Hi!

I have just registered and am trying to decide which FEZ product to buy. I am attracted to the single chip USBizi based products, but am worried by the low amounts of user-available memory (particularly RAM but also flash). I read in one Microsoft paper that the framework will run in “as little as 300kb” of RAM while USBizi has only 96kb! The fact that the EMX devices have so very much more memory is also a little concerning.

But then I see the new Panda II running a full Ethernet stack including web server AND a graphics touch-screen at the same time! So it seems like the USBizi chips somehow manage within these very tight constraints!

Any comments would be appreciated: does the USBizi feel claustrophobic from the developer’s perspective? Are you constantly having to scrimp for RAM like on an 8-bit PIC chip? Once you have loaded up drivers for all the on-chip peripherals (e.g. CAN) are you running out of flash for the application code?

John


#2

USBizi is fine. You’d be lucky to hit the memory limit in a real application.

I think Gus has a standing comment - he’s waiting for the first real world project that hits the memory limit and I’m sure there’d be a prize in it :slight_smile:

Having said that, Cobra is an awesome platform and you shouldn’t hesitate to jump there - the fact that it has integrated ethernet is a plus in my view, no shield so it’s a fully self contained device with a great touch screen


#3

MS say it needs as little as 300KB of FLASH, not RAM. USBizi has 512kb or flash so ram is pretty much all yours.


#4

Good question that deserves a detailed answer…let us add something to FAQ and we will get back to you on this.


#5

Here you go. I hope this helps http://www.tinyclr.com/faq/#21


#6

I’ve hit it with Pyxis loading a combobox with a few hundred items.

BTW; hitting that memory limit and really hurt if you’re not careful. I managed to leak out of where I should be and screw a few things up. Luckily it’s easy to recover there.


#7

Thanks Gus, that is very helpful and it looks like the USBizi boards will be fine for my application.