Book recommendation

[Paulo Ricardo Pabst]

Hi,

I'm new on this group. I'm starting my final year's project and I'm building a "interpolated multi-axis controller" (aka NC controller).

I will use a FPGA (probably an spartan 3) to build a DDS, a quadrature encoder interface and some others digital circuits.

My knowledge about VHDL is not really good, I'd read some tutorials about VHDL and I played with VHDL a little. But what I don't know is the best way to implement these digital circuits.

So, what I want is some suggestions about what book I need to buy to learn how implement configuration registers, QEI, DDS, microcontroller interface, etc. I see some books on amazon, but I'm still in doubt about them.

TIA,
Paulo Ricardo.

 

[Paulo Ricardo Pabst]

Em quarta-feira, 9 de outubro de 2013 10h48min08s UTC-7, Tim Wescott escreveu:

On Wed, 09 Oct 2013 10:02:43 -0700, Paulo Ricardo Pabst wrote:



Hi,



I'm new on this group. I'm starting my final year's project and I'm

building a "interpolated multi-axis controller" (aka NC controller).



I will use a FPGA (probably an spartan 3) to build a DDS, a quadrature

encoder interface and some others digital circuits.



My knowledge about VHDL is not really good, I'd read some tutorials

about VHDL and I played with VHDL a little. But what I don't know is the

best way to implement these digital circuits.



So, what I want is some suggestions about what book I need to buy to

learn how implement configuration registers, QEI, DDS, microcontroller

interface, etc. I see some books on amazon, but I'm still in doubt about

them.



How much do you know about digital design already? A good VHDL book

isn't going to tell you much about digital design -- it's going to tell

you how, after you know what you want, you can translate that desire into

VHDL. So if your first problem is that you have no clue what a DDS, a

quadrature encoder interface, and those other digital circuits should do,

then your primary need is not a VHDL book.



If that's the case, then you want to look for a book with a title that's

more along the line of "Digital Logic Design (with VHDL)"; i.e., you want

a book about digital logic design that uses VHDL to convey the design

content. This will fill in your most crying need, and hopefully give you

enough VHDL chops to get you by.



The book on my shelf is the opposite. It's "The Designer's Guide to VHDL"

by Peter Ashenden, and its meant for people who know digital design, but

not VHDL.



Keep in mind, though, that I'm no VHDL expert, and the book was just the

likeliest-looking one at Powell's when I went shopping. I'd look to it

only if no one else coughs up a title. It proved adequate to what I was

doing, but what I was doing was largely showing that an algorithm was

feasible _at all_; once I had a first cut working the real FPGA designers

on the project took it out of my hands and made it work with fewer gates

and at a higher clock rate and all that good stuff.



Unless your prof is demanding that you do this with an FPGA, or unless

you want to use an FPGA just because, you may want to consider

implementing those functions on the microcontroller that you're

interfacing with. I'm certainly not saying you definitely _should_ --

I've just found that it's often cheaper to pull moderate-speed "logic"

functions into the micro, particularly if I'm at liberty to shop for the

microprocessor I need (for instance: many micros these days are made

specifically for motor control, and have quadrature encoder interfaces

built in).



--



Tim Wescott

Wescott Design Services

http://www.wescottdesign.com

Tim,

Thanks for quick answer. I've 12 years of experience in electronics design. So I able to do digital design and I know a little of VHDL. What I need is a book that teaches me the best way to make the project. I need to learn how to "...make it work with fewer gates and at a higher clock rate and all that good stuff."

Paulo.

 

[Tim Wescott]

On Wed, 09 Oct 2013 10:02:43 -0700, Paulo Ricardo Pabst wrote:

Hi,

I'm new on this group. I'm starting my final year's project and I'm
building a "interpolated multi-axis controller" (aka NC controller).

I will use a FPGA (probably an spartan 3) to build a DDS, a quadrature
encoder interface and some others digital circuits.

My knowledge about VHDL is not really good, I'd read some tutorials
about VHDL and I played with VHDL a little. But what I don't know is the
best way to implement these digital circuits.

So, what I want is some suggestions about what book I need to buy to
learn how implement configuration registers, QEI, DDS, microcontroller
interface, etc. I see some books on amazon, but I'm still in doubt about
them.

How much do you know about digital design already? A good VHDL book
isn't going to tell you much about digital design -- it's going to tell
you how, after you know what you want, you can translate that desire into
VHDL. So if your first problem is that you have no clue what a DDS, a
quadrature encoder interface, and those other digital circuits should do,
then your primary need is not a VHDL book.

If that's the case, then you want to look for a book with a title that's
more along the line of "Digital Logic Design (with VHDL)"; i.e., you want
a book about digital logic design that uses VHDL to convey the design
content. This will fill in your most crying need, and hopefully give you
enough VHDL chops to get you by.

The book on my shelf is the opposite. It's "The Designer's Guide to VHDL"
by Peter Ashenden, and its meant for people who know digital design, but
not VHDL.

Keep in mind, though, that I'm no VHDL expert, and the book was just the
likeliest-looking one at Powell's when I went shopping. I'd look to it
only if no one else coughs up a title. It proved adequate to what I was
doing, but what I was doing was largely showing that an algorithm was
feasible _at all_; once I had a first cut working the real FPGA designers
on the project took it out of my hands and made it work with fewer gates
and at a higher clock rate and all that good stuff.

Unless your prof is demanding that you do this with an FPGA, or unless
you want to use an FPGA just because, you may want to consider
implementing those functions on the microcontroller that you're
interfacing with. I'm certainly not saying you definitely _should_ --
I've just found that it's often cheaper to pull moderate-speed "logic"
functions into the micro, particularly if I'm at liberty to shop for the
microprocessor I need (for instance: many micros these days are made
specifically for motor control, and have quadrature encoder interfaces
built in).

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[Tom Gardner]

On 09/10/13 21:07, Paulo Ricardo Pabst wrote:

Thanks for quick answer. I've 12 years of experience
in electronics design. So I able to do digital design
and I know a little of VHDL. What I need is a book that
teaches me the best way to make the project. I need to
learn how to "...make it work with fewer gates and at
a higher clock rate and all that good stuff."

Since I haven't used VHDL before, I /am/ interested in
pointers to VHDL "style guides", by which I mean:
- coding patterns and anti-patterns
- clean directory tree structures for libraries and packages
- anything else that helps me avoid messy pitfalls
I have seen a few such style guides around, but none
of them are really satisfying!

I have more years electronic experience than I care to
recall, so I'll figure out ways to condense logic and
speed up logic (in my experience each device manufacturer
tends to produce good info about their devices).

 

[glen herrmannsfeldt]

Paulo Ricardo Pabst <prpabst@gmail.com> wrote:

(snip)

Thanks for quick answer. I've 12 years of experience in
electronics design. So I able to do digital design and I know
a little of VHDL. What I need is a book that teaches me the
best way to make the project. I need to learn how to "...make
it work with fewer gates and at a higher clock rate and all
that good stuff."

For FPGAs logic optimization is a little different from the
TTL days. For one, any four intput (or, now, 6 input) one output
logic block can be implemented in an LUT. More important for
speed and high clock rates is pipelining, also because FPGAs
have FFs on each LUT output. (At least many do.)

There used to be books on the architecture of pipelined computers,
from the days of the IBM 360/91 and Cray-1. Some of the ideas
still work, and some don't.

The optimizations that the synthesis tools do make it hard to know
which things you need to know and which you don't.

I don't know of any books on optimization for FPGAs, but that
doesn't mean that there aren't any.

-- glen

 

[Svenn Are Bjerkem]

I have been programming FPGA with VHDL for some years now. I came from high-speed full-custom and digital standard cell semiconductor design with cadence and that was 100% schematic capture.

I have two books:
FPGA prototyping by VHDL examples, by Pong P. Chu
Circuit Design with VHDL, by Volnei A. Pedroni.

Both books gave me a good introduction to the procedure of mapping something structural (schematic, block diagram) into something behavioural (RTL, FSM), and at the same time cover something I knew, real hardware.

Chu is using Xilinx and Pedroni seems agnostic.

Chu has a short tutorial on a Xilinx project to get started with the toolchain, and Pedroni has tutorials for Xilinx and Altera. I didn't follow any of these tutorials as I pretty much understood the FPGA tools by previous tool experience.

You can have a peek into both books at google books.

Pedroni has a lot of examples on how to use types, both working examples and examples which will not work. That's the section I use most nowadays.

Other than that, Xilinx has some documents on coding style, both for esthetics and for speed. Google for "xilinx coding guidelines" as they are hidden in obscure places.

The switch from schematic structural thinking to VHDL behavioural thinking sometimes lead to horrible code. The above books helped me through that period, specially regarding use of clock enable instead of gated clocks and avoid inferring unwanted latches. Just remember to replace the clk'event and clk='1' with the modern rising_edge(clk) in the textbook examples.

The biggest hurdle was to accept that the synthesizer could do a better job than me and stop being too clever during design.

--
Svenn

 

[MK]

On 09/10/2013 18:48, Tim Wescott wrote:

On Wed, 09 Oct 2013 10:02:43 -0700, Paulo Ricardo Pabst wrote:

Hi,

I'm new on this group. I'm starting my final year's project and I'm
building a "interpolated multi-axis controller" (aka NC controller).

I will use a FPGA (probably an spartan 3) to build a DDS, a quadrature
encoder interface and some others digital circuits.

My knowledge about VHDL is not really good, I'd read some tutorials
about VHDL and I played with VHDL a little. But what I don't know is the
best way to implement these digital circuits.

So, what I want is some suggestions about what book I need to buy to
learn how implement configuration registers, QEI, DDS, microcontroller
interface, etc. I see some books on amazon, but I'm still in doubt about
them.

How much do you know about digital design already? A good VHDL book
isn't going to tell you much about digital design -- it's going to tell
you how, after you know what you want, you can translate that desire into
VHDL. So if your first problem is that you have no clue what a DDS, a
quadrature encoder interface, and those other digital circuits should do,
then your primary need is not a VHDL book.

If that's the case, then you want to look for a book with a title that's
more along the line of "Digital Logic Design (with VHDL)"; i.e., you want
a book about digital logic design that uses VHDL to convey the design
content. This will fill in your most crying need, and hopefully give you
enough VHDL chops to get you by.

The book on my shelf is the opposite. It's "The Designer's Guide to VHDL"
by Peter Ashenden, and its meant for people who know digital design, but
not VHDL.

Keep in mind, though, that I'm no VHDL expert, and the book was just the
likeliest-looking one at Powell's when I went shopping. I'd look to it
only if no one else coughs up a title. It proved adequate to what I was
doing, but what I was doing was largely showing that an algorithm was
feasible _at all_; once I had a first cut working the real FPGA designers
on the project took it out of my hands and made it work with fewer gates
and at a higher clock rate and all that good stuff.

Unless your prof is demanding that you do this with an FPGA, or unless
you want to use an FPGA just because, you may want to consider
implementing those functions on the microcontroller that you're
interfacing with. I'm certainly not saying you definitely _should_ --
I've just found that it's often cheaper to pull moderate-speed "logic"
functions into the micro, particularly if I'm at liberty to shop for the
microprocessor I need (for instance: many micros these days are made
specifically for motor control, and have quadrature encoder interfaces
built in).

I'm with Tim on this - use a micro if you can.

I've found all books on VHDL or Verilog to be deeply disappointing. The
best/quickest way to get started in a goodish direction is to go on a
course but it's not cheap.

I've been using VHDL for years (started with a 1 week course by Esperan
who don't exist any more.) The only book I have which I would even
slightly recommend is VHDL 2008 Just the New Stuff by Ashenden and
Lewis. It's NOT a book to start with.

If you have to do it all on your own trawl the web - there is a lot of
"very first step" stuff and quite a lot of useful more advanced material
but it can be hard sorting the good from the bad.
At least it's free.

(The last Verilog book I bought was over ÂŁ100 and its just trash.)

BTW if you are at Uni aren't they meant to TEACH you the basic stuff ?

Good luck !

Michael Kellett

 

[HT-Lab]

On 10/10/2013 09:46, MK wrote:

...

I've been using VHDL for years (started with a 1 week course by Esperan
who don't exist any more.)

they are still alive and kicking...

Hans
www.ht-lab.com

 

[Paulo Ricardo Pabst]

Em quinta-feira, 10 de outubro de 2013 08h07min48s UTC-7, MK escreveu:

On 10/10/2013 10:38, HT-Lab wrote:

On 10/10/2013 09:46, MK wrote:



..



I've been using VHDL for years (started with a 1 week course by Esperan

who don't exist any more.)



they are still alive and kicking...



Hans

www.ht-lab.com







Well so they are - I was sure they'd gone. Perhaps I'll ask them about

their Verilog for VHDL users course.



Michael Kellett

Thanks for all replies. I will read some articles and look into some open source IP cores (for learning, not for plagiarize). I decided to use FPGA because I need 4 channels QEI, 4 channels DDS and another small logic.

-- Paulo

 

[MK]

On 10/10/2013 10:38, HT-Lab wrote:

On 10/10/2013 09:46, MK wrote:

..

I've been using VHDL for years (started with a 1 week course by Esperan
who don't exist any more.)

they are still alive and kicking...

Hans
www.ht-lab.com

Well so they are - I was sure they'd gone. Perhaps I'll ask them about
their Verilog for VHDL users course.

Michael Kellett

 

[glen herrmannsfeldt]

Svenn Are Bjerkem <svenn.bjerkem@googlemail.com> wrote:

(snip)

The switch from schematic structural thinking to VHDL behavioural
thinking sometimes lead to horrible code. The above books helped
me through that period, specially regarding use of clock enable
instead of gated clocks and avoid inferring unwanted latches.
Just remember to replace the clk'event and clk='1' with the
modern rising_edge(clk) in the textbook examples.

I mostly write structural verilog, though behavioral for FFs
(the only way I know) and usually behavioral for state machines.

The biggest hurdle was to accept that the synthesizer could do
a better job than me and stop being too clever during design.

Yes, this one I agree with. Though they don't find everything,
there are many cases where they can do well with more obvious,
and not so efficient looking, code.

-- glen

 

[Tom Gardner]

On 10/10/13 09:47, Svenn Are Bjerkem wrote:

I have been programming FPGA with VHDL for some years now. I came from high-speed full-custom and digital standard cell semiconductor design with cadence and that was 100% schematic capture.

I have two books:
FPGA prototyping by VHDL examples, by Pong P. Chu
Circuit Design with VHDL, by Volnei A. Pedroni.

Both books gave me a good introduction to the procedure of mapping something structural (schematic, block diagram) into something behavioural (RTL, FSM), and at the same time cover something I knew, real hardware.

Thanks, I'll have a look.


> Chu has a short tutorial on a Xilinx project to get started with the toolchain, and Pedroni has tutorials for Xilinx and Altera. I didn't follow any of these tutorials as I pretty much understood the FPGA tools by previous tool experience.

I'm sure I'll figure out the toolchain basics fairly quickly,
but I'm less convinced about the subtleties. I'm hoping
100 power tips for fpga designers" by Evgeni Stavinov
will give me some clues.


> Other than that, Xilinx has some documents on coding style, both for esthetics and for speed. Google for "xilinx coding guidelines" as they are hidden in obscure places.

I've tried "xilinx style guide", but that's a useful alternative term.

The switch from schematic structural thinking to VHDL behavioural thinking sometimes lead to horrible code. The above books helped me through that period, specially regarding use of clock enable instead of gated clocks
Not concerned about avoiding that trap

and avoid inferring unwanted latches.
....but that trap is more subtle

> Just remember to replace the clk'event and clk='1' with the modern rising_edge(clk) in the textbook examples.

I've read there are subtle differences, but I've forgotten what they are! "rising_edge(clk)" is terser.


> The biggest hurdle was to accept that the synthesizer could do a better job than me and stop being too clever during design.

I haven't of course, calibrated my definition of "too clever".
My current presumption is that I'll use behavioural code except
where I've decided I need a specific "high level" primitive
provided by the device manufacturer.