Mike Treseler <[email protected]> writes:

> Chris Maryan wrote:
>
>> If cost is a concern, you can ditch the boards all together and do the
>> whole thing in simulation. Put Altera's free Quartus II web edition
>> software on a PC and teach from that. The waveform simulation is quite
>> good for instruction purposes.
>
> Exactly. To learn vhdl, all I need is
> 1. A simulator to prove that my code is functional, and
> 2. Synthesis software to verify that my code
> synthesizes, fits, and makes Fmax.
> Flashing the LED on the board is just icing on the cake.

That assumes that all you want to do is flash an LED - as soon as you
have something more complex to interface to you have the problem of
getting models. Often you write your own, which means simulation
works fine (after all, I wrote both sides of the interface, it's bound
to work together). It's not until you try it on real hardware that
you discover where the holes inyour model of external devices are.

Also, there's something fulfilling (in the early days at least) of
seeing real lights flashing. I remember my first VHDL course - we
"made" a digital clock, but all in simulation - it didn't feel like
I'd achieved anything. The icing can be very tasty :-)

>> This may seem obvious
>> but our problem is finding time in the curriculum to do this on top of
>> dealing with the real course content (processor architecture).
>
> Why is always a candy machine or a processor?

I like non-framebuffer video demos - hook up a pin each to RGB, VS and
HS of a VGA monitor

* First make the sync pulses.
* Draw a box around the edge of the screen (good for catching off-by-one
errors in the counters and decode when you get a 2 pixel line down one
side :-)

Work up from there -
* Make a pixel "bounce" around the screen
* Make it a circular blob
* All the way up to doing a pong game
- put scores up, read some up/down switches (or even pots),
multicolour, on-the-fly 3d-rendering (well, for the advanced
student
* Put in a coin slot and you could even have the coin-counting state-
machine so beloved of academia before you get to play a game :-)

Cheers,
Martin

--
[email protected]
TRW Conekt - Consultancy in Engineering, Knowledge and Technology
http://www.conekt.net/electronics.html