[NTLK] Einstein on Raspbeiiy Pi

[Matthias Melcher]

On 25.09.2012, at 06:10, Alex Perez <aperez at alexperez.com> wrote:
>> 
>> "I have a Raspberry Pi and it is quite cool just how powerful it is for
>> such a tiny inexpensive package.  Haven't had time to do much of
>> anything with it yet, though."
>> 
>> I haven't heard if there's any touchscreen hardware compatible with
>> it.  As far as video it only comes with composite and HDMI video outs,
>> so not quite ready to be a handheld out of the box.
>> 
> 
> This is factually incorrect. There is a MIPI DSI port on the Raspberry 
> Pi, with the intention that ribbon cable can be direct-attached. See 
> http://elinux.org/RPi_Screens#DSI_port 

OK, thanks for the link to all teh Pi documentation. Even though I did not find (yet) enough in-depth schematics to compare teh MP and Pi bit-by-bit, I feel confident to say this:

The RPi is a great piece of hardware! It is well thought through and amazingly cheap. It has some features that I did not expect at all (Hardware OpenGL), but lacks a few that I find obvious, like Power over Ethernet.

But in any case, what a great machine.

The MessagePad is less powerful in evry way, generally by the factor 5 to 10. The CPU is a predecessor of the RPi one, understanding a subset of whatever RPi offers. But the MP is also so much more in respect to portability, energy consumption, display and usability. It's a whole package vs. an experimental board.

So on the hardware side, after adding a battery compartment, a case, a screen, a touch sensitive board, etc. The RPi is probably more expensive than the MP2100 on EBay in pristine condition.

The RPi outputs color, is faster and has more RAM, but none of that is usable by the NewtonOS unless we modify the OS. And that means we have to understand the OS and translate parts of it. A few things we would have to understand and rewrite are: 
 - the MMU control, because RAM is not where it is in the MP
 - the screen driver
 - the touch sensitive field driver
 - the Flash driver (PCMCIA to SD)
 - the interrupt system
 - the serial port driver
 - the battery and power management
 - the audio driver (and with it, DMA system)

At this point, we would still not make any use of the ethernet, the additional video features, or the huge RAM. We would miss the real time clock though.


My conclusion: patching NewtonOS to run on the RPi will take years.

My suggestion: if anyone has the time available to port NewtonOS to RPi, don't. INstead, help us to make the Einstein simulator better. This will generate license free C++ source code that anyone can ready, use, and even improve.

My solution: RPi runs Linux. It is quite easy to compile Einstein for RPi. It will be slow, but it works pretty much out of the box.

 - Matthias