BBC Second Processor Tube ULA (was Re: What kind of IC is this)

[Alexandre Souza]

> The problem is that very few people have both a grasp on that knowledge 
> and
> the ability to do the necessary electronic design - it's only really worth 
> it
> for a drop-in replacement (i.e. a single chip or a very small 
> daughter-board
> to plug into the ULA's 40-pin to DIP socket) because (as Phil says) it'd 
> be a
> reasonably large board to do it as discrete logic.

    This knowledge should be shared...One of the things I plan to do when I 
learn VHDL is to create a "for dummies" tutorial. But, if someone knows how 
to create a circuit using ttl gates, you can use one of the manufacturers' 
tools to change it to vhdl/bitstream. I use an altera tool where I can enter 
my design in schematics. All cpld/fpga manufacturers has this option.