Raspberry Pi, GNAT, and ee9

Raspberry Pi, GNAT, and ee9

[Bill Findlay]

The Raspberry Pi is a very small ARM-based computer designed to stimulate
interest in programming.

If you had not heard about it, have a look here:
<http://www.raspberrypi.org/faqs>

Bill Gallacher has one and he thought of ee9, my KDF9 emulator in Ada 2005.

His Raspberry Pi runs Debian Linux, which supports Ada, so he set to work
this afternoon, and -- Abracadabra! -- he can now run KDF9 software on a
machine that fits in a shirt pocket.  It's not quite an iPhone, but it's
getting there!

The Raspberry Pi is about 60-70 times slower than my 2.3GHz Core i7 Macbook
Pro, but that is about 3-5 times faster than the real KDF9 was 50 years ago.

I hope I'll be able to add Raspberry Pi to my roster of ee9 distributions
very soon.

There was one glitch: one of the source code modules causes a compiler
Storage_Error exception, when compiled with optimization level >= -O1.
Compiling that module separately at -O0 allows the rest of the 20KSLOC to
build normally.  It's not yet clear whether the problem is lack of stack
space (the RAM is only [!] 256MB), or a bug in the GCC optimiser.

-- 
Bill Findlay
with blueyonder.co.uk;
use  surname & forename;

Re: Raspberry Pi, GNAT, and ee9

[Simon Wright]

Bill Findlay <yaldnif.w@blueyonder.co.uk> writes:

> The Raspberry Pi is a very small ARM-based computer designed to
> stimulate interest in programming.
>
> If you had not heard about it, have a look here:
> <http://www.raspberrypi.org/faqs>
>
> Bill Gallacher has one and he thought of ee9, my KDF9 emulator in Ada
> 2005.

I have one of these, too. Sweet.

I've created a Sourceforge project[1] so I can drive the I2C bus (and
specifically the MCP23017 I/O expander).

No releases yet, and no writeup of the software, but it's been an
interesting exercise.

I'd like to make the library interrupt-driven, but that's not so easy on
Raspbian(!) Linux, so for the moment it detects input (switch) changes
by polling.

[1] http://raspi-i2c-ada.sourceforge.net/