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Hi,

Complete newbie to VHDL.
I am electronics engineer and want to
start learning and doing VHDL.

I can learn from googling but to cut out
the noise, just wondered if anyone can
give me some clues.

I'm on the GNU/Linux platform.
Cheapest way to buy a chip and
program it with something like
the free 6502 CPU. Then edit the
VHDL and program it again and again
to see how VHDL works.

e7 < k> wrote in message news:<nn4Pc.17502$. uk>...

> I'm on the GNU/Linux platform.
> Cheapest way to buy a chip and
> program it with something like
> the free 6502 CPU. Then edit the
> VHDL and program it again and again
> to see how VHDL works.

Unless you just want to just run the canned demos
and flash some LEDs, consider deferring the hardware
purchase until you learn some vhdl language for synthesis
and simulation.

Once you have a synthesis design that sims,
doing the place and route and loading an FPGA
image on a board is pretty cut and dry.

Work with the free sonata linux download
to design some synth code
and a working simulation testbench.

-- Mike Treseler

Mike Treseler wrote:

> e7 < k> wrote in message
> news:<nn4Pc.17502$. uk>...
>
>> I'm on the GNU/Linux platform.
>> Cheapest way to buy a chip and
>> program it with something like
>> the free 6502 CPU. Then edit the
>> VHDL and program it again and again
>> to see how VHDL works.
>
> Unless you just want to just run the canned demos
> and flash some LEDs, consider deferring the hardware
> purchase until you learn some vhdl language for synthesis
> and simulation.

Mike, my experience of VHDL is nil.
So even canned demos are going to sound great.
Even just to buy a chip, and flash an LED on/off
will be a great start for a newbie like me.
But I haven't the foggiest which makers are best
place to start. I googled for all the major vendors,
but I am a loss with the bewildering array of information.

I just want a cheap skate DIP chip something commonly used
that I can solder up some sockets pretty quick, and
some way of programming it,
and then Linux based software that can convert
VHDL into schematics / vice versa and then program it
so that I can see it working.
I think the free 6502 uses 15,000 cells or something, so I need
something big enough to cope with that.


> Once you have a synthesis design that sims,
> doing the place and route and loading an FPGA
> image on a board is pretty cut and dry.
>
> Work with the free sonata linux download
> to design some synth code
> and a working simulation testbench.

I will give that a try - thank you.

> -- Mike Treseler

e7 wrote:


> Mike, my experience of VHDL is nil.

> I think the free 6502 uses 15,000 cells or something, so I need
> something big enough to cope with that.

Do you think, that such a big project will help you? I personally would
get confused.

I would recommend to start with a book, like HDL chip design
http://www.doone.com/hdl_chip_des.html Turn your computer off and just
read. This books wasn't that heavy, but very helpful.


Ralf

Ralf Hildebrandt wrote:

> e7 wrote:
>
>
>> Mike, my experience of VHDL is nil.
>
>> I think the free 6502 uses 15,000 cells or something, so I need
>> something big enough to cope with that.
>
> Do you think, that such a big project will help you? I personally would
> get confused.

I do a lot of coding in assembler and C - so learning VHDL is
easy enough having looked at the syntax - but need to link
it with the real world by programming chips and try to
understand the practical side of using VHDL, programming up
the chips and then debugging it when it all goes horrible.


> I would recommend to start with a book, like HDL chip design
> http://www.doone.com/hdl_chip_des.html Turn your computer off and just
> read. This books wasn't that heavy, but very helpful.
>
>
> Ralf

Thanks - but didn't want to spend money like that.
If there are good on-line books, I'll take it.

e7 < k> wrote:
> Ralf Hildebrandt wrote:
>
>> e7 wrote:
>>
>>
>>> Mike, my experience of VHDL is nil.
>>
>>> I think the free 6502 uses 15,000 cells or something, so I need
>>> something big enough to cope with that.
>>
>> Do you think, that such a big project will help you? I personally would
>> get confused.
>
> I do a lot of coding in assembler and C - so learning VHDL is
> easy enough having looked at the syntax - but need to link
> it with the real world by programming chips and try to
> understand the practical side of using VHDL, programming up
> the chips and then debugging it when it all goes horrible.

Just one thing to remember with VHDL, the key is the HDL part, thats
H=Hardware D=Descriptor L=Language.

Just FYI the V in VHDL stands for VLSI which stands for very large scale
intergration.

Avoid thinking of VHDL as code but more as a picture of the hardware you
are trying to implement. Otherwise, you'll run into all sorts of timing
problems.

One more thing, you can actually decribe hardware in C. But as with VHDL,
don't think of it as code but a description of the hardware you are trying
to implement. Personally for simple designs, I perfer to use a graphical
layout program, that way the temptations of looking at the problem like
a programmer is reduced.
--

Wing Wong.
Webpage: http://wing.ucc.asn.au

e7 wrote:

> Mike, my experience of VHDL is nil.
> So even canned demos are going to sound great.
> Even just to buy a chip, and flash an LED on/off
> will be a great start for a newbie like me.

If your objective is to program a circuit board
to do your bidding, consider buying a CPU board
that boots right out of the box.

If you objective is to learn vhdl, start with
just a simulator.

> But I haven't the foggiest which makers are best
> place to start. I googled for all the major vendors,
> but I am a loss with the bewildering array of information.

FPGAs are a medium-to-big bag of gates and flops.
You have to connect the dots, either
with a schematic or an text description.

> I just want a cheap skate DIP chip something commonly used
> that I can solder up some sockets pretty quick,

DIP components are rare and cheap sockets are intermittent.

> and some way of programming it,
> and then Linux based software that can convert
> VHDL into schematics / vice versa and then program it
> so that I can see it working.

Without an hdl design and working simulation testbench,
the odds are you will see it not working.

> I think the free 6502 uses 15,000 cells or something, so I need
> something big enough to cope with that.

Consider either a real cpu board or a much simpler
hardware objective. Good luck.

-- Mike Treseler

e7 wrote:


>>Do you think, that such a big project will help you? I personally would
>>get confused.

> I do a lot of coding in assembler and C - so learning VHDL is
> easy enough having looked at the syntax
....

NACK. VHDL is not a programming language. It is a tool for modelling
digital circuits. Do not program you circuits - model them!

Software is a strictly sequential task, while a HDL is more a parallel
task. A HDL is similar to a CAD program with the difference, that it is
text-based and not graphically.


O.k. - VHDL and especially synthesizable VHDL is simple and you can do a
lot with only the modelling template for a flipflop, latch and
combinational logic, but especially this has nothing in common with
software.

Sometimes, when I have to write a program (C or ASM), then I first think
of a HDL-like solution and then have to throw it completely away,
because software is really different.


Ralf

Ralf Hildebrandt <Ralf-> wrote:
> e7 wrote:
>
>
>>>Do you think, that such a big project will help you? I personally would
>>>get confused.
>
>> I do a lot of coding in assembler and C - so learning VHDL is
>> easy enough having looked at the syntax
> ...
>
> NACK. VHDL is not a programming language. It is a tool for modelling
> digital circuits. Do not program you circuits - model them!

As I said in an earlier post remember the HDL in VHDL stands for hardware
DESCRIPTOR language, meaning its a language used to describe hardware. As
Ralf implied, if you think of VHDL as code you'll bound to run into problems.

--

Wing Wong.
Webpage: http://wing.ucc.asn.au

Wing Fong Wong wrote:

> Ralf Hildebrandt <Ralf-> wrote:
>> e7 wrote:
>>
>>
>>>>Do you think, that such a big project will help you? I personally would
>>>>get confused.
>>
>>> I do a lot of coding in assembler and C - so learning VHDL is
>>> easy enough having looked at the syntax
>> ...
>>
>> NACK. VHDL is not a programming language. It is a tool for modelling
>> digital circuits. Do not program you circuits - model them!
>
> As I said in an earlier post remember the HDL in VHDL stands for hardware
> DESCRIPTOR language, meaning its a language used to describe hardware. As
> Ralf implied, if you think of VHDL as code you'll bound to run into
> problems.

I have enough understanding to follow VHDL modelling.
What I now want to do is make something with it.
Something readily available off the shelf to start
programming a chip and test things.