Comments on: Simulating a quadrature decoder with LTSpice and what has become of it http://blog.spitzenpfeil.org/wordpress/2009/02/10/simulating-a-quadrature-decoder-with-ltspice-and-what-has-become-of-it/ "Another visitor! Stay a while. Staaaaay, FOREVER!" Thu, 11 Mar 2010 07:08:45 +0100 http://wordpress.org/?v=2.9.2 hourly 1 By: robert http://blog.spitzenpfeil.org/wordpress/2009/02/10/simulating-a-quadrature-decoder-with-ltspice-and-what-has-become-of-it/#comment-115 robert Sat, 28 Feb 2009 21:37:40 +0000 http://blog.spitzenpfeil.org/wordpress/?p=868#comment-115 Well my friend, thank you for showing me the 'right way'. It's always nice to be reminded of the good old RTFM. If I had really wanted to thrash LTSpice you would have noticed. I'd prefer non standard behaviour of gates to be pointed out more clearly, that is NOT having to dig through the manpage. Defaulting the delay Td of a logical gate to zero is questionable. It would be more helpful to make these parameters clearly visible by adding a line with "Td=0, Z=..." for setting default values. Well my friend, thank you for showing me the ‘right way’. It’s always nice to be reminded of the good old RTFM.

If I had really wanted to thrash LTSpice you would have noticed.

I’d prefer non standard behaviour of gates to be pointed out more clearly, that is NOT having to dig through the manpage.

Defaulting the delay Td of a logical gate to zero is questionable. It would be more helpful to make these parameters clearly visible by adding a line with “Td=0, Z=…” for setting default values.

]]> By: analogspiceman http://blog.spitzenpfeil.org/wordpress/2009/02/10/simulating-a-quadrature-decoder-with-ltspice-and-what-has-become-of-it/#comment-114 analogspiceman Sat, 28 Feb 2009 18:46:49 +0000 http://blog.spitzenpfeil.org/wordpress/?p=868#comment-114 Before having indulged your ignorance with your misguided attempt at trashing LTspice, you really should have made the small effort required to read the LTspice Help file topic on digital a-devices (Help -> LTspice -> Circuit Elements -> A. Special Functions). Had you done so, you would have seen the following: "The propagation delay defaults to zero and is set with instance parameter Td. Input hold time is equal to the propagation delay." And: "The exclusive XOR device has non-standard behavior when more than two inputs are used: The output is true only when exactly one of all inputs is true. Use the associative property of XOR's with multiple XOR devices to implement an XOR block with more than two inputs." Rather than blogging testimonials to your own techno-tool laziness, you might consider joining the LTspice Yahoo users' group. It's very active, offers more useful support than most for-pay groups, has a huge archive of circuits and tips and is open to all, beginners and experts alike, with an interest in LTspice. http://tech.groups.yahoo.com/group/LTspice See you there! - a.s. Before having indulged your ignorance with your misguided attempt at trashing LTspice, you really should have made the small effort required to read the LTspice Help file topic on digital a-devices (Help -> LTspice -> Circuit Elements -> A. Special Functions). Had you done so, you would have seen the following:

“The propagation delay defaults to zero and is set with instance parameter Td. Input hold time is equal to the propagation delay.”

And:

“The exclusive XOR device has non-standard behavior when more than two inputs are used: The output is true only when exactly one of all inputs is true. Use the associative property of XOR’s with multiple XOR devices to implement an XOR block with more than two inputs.”

Rather than blogging testimonials to your own techno-tool laziness, you might consider joining the LTspice Yahoo users’ group. It’s very active, offers more useful support than most for-pay groups, has a huge archive of circuits and tips and is open to all, beginners and experts alike, with an interest in LTspice.

http://tech.groups.yahoo.com/group/LTspice

See you there! – a.s.

]]> By: Keith Neufeld http://blog.spitzenpfeil.org/wordpress/2009/02/10/simulating-a-quadrature-decoder-with-ltspice-and-what-has-become-of-it/#comment-109 Keith Neufeld Thu, 12 Feb 2009 17:44:11 +0000 http://blog.spitzenpfeil.org/wordpress/?p=868#comment-109 I've been lucky on my projects and the internal Schmitt triggers have been good enough to do analog conversions for me. My sympathies to you. :-) I’ve been lucky on my projects and the internal Schmitt triggers have been good enough to do analog conversions for me. My sympathies to you. :-)

]]> By: robert http://blog.spitzenpfeil.org/wordpress/2009/02/10/simulating-a-quadrature-decoder-with-ltspice-and-what-has-become-of-it/#comment-108 robert Wed, 11 Feb 2009 15:29:56 +0000 http://blog.spitzenpfeil.org/wordpress/?p=868#comment-108 Nice, I'll consider this when I use a rotary encoder button next time. And it's about time I familiarize myself with creating and really understanding classes/objects in C++, not just using them :-) Your code accepts encoders on all the digital pins of the Arduino, but in this little project I had to use analog reads. User adjustments on the sensor hardware itself had to be avoided at all cost. It is only good enough for hand wheels and maxes out at about 50Hz tick frequency (about 1 revolution per second). Nice, I’ll consider this when I use a rotary encoder button next time. And it’s about time I familiarize myself with creating and really understanding classes/objects in C++, not just using them :-)

Your code accepts encoders on all the digital pins of the Arduino, but in this little project I had to use analog reads. User adjustments on the sensor hardware itself had to be avoided at all cost. It is only good enough for hand wheels and maxes out at about 50Hz tick frequency (about 1 revolution per second).

]]> By: Keith Neufeld http://blog.spitzenpfeil.org/wordpress/2009/02/10/simulating-a-quadrature-decoder-with-ltspice-and-what-has-become-of-it/#comment-107 Keith Neufeld Wed, 11 Feb 2009 14:46:54 +0000 http://blog.spitzenpfeil.org/wordpress/?p=868#comment-107 I don't know whether you're interested, but I had posted an Arduino library to do quadrature decoding in the timer2 interrupts as well. I took the time to encapsulate it into a class so you can do things like: #include "Quadrature.h" Quadrature myencoder1(9, 10); // Connected to pins 9 and 10 ... x = myencoder1.position(); Might be of interest to you. http://www.neufeld.newton.ks.us/electronics/?page_id=249 Thanks for the blogroll, BTW! I don’t know whether you’re interested, but I had posted an Arduino library to do quadrature decoding in the timer2 interrupts as well. I took the time to encapsulate it into a class so you can do things like:

#include “Quadrature.h”
Quadrature myencoder1(9, 10); // Connected to pins 9 and 10
…
x = myencoder1.position();

Might be of interest to you.

http://www.neufeld.newton.ks.us/electronics/?page_id=249

Thanks for the blogroll, BTW!

]]> By: robert http://blog.spitzenpfeil.org/wordpress/2009/02/10/simulating-a-quadrature-decoder-with-ltspice-and-what-has-become-of-it/#comment-106 robert Wed, 11 Feb 2009 13:58:16 +0000 http://blog.spitzenpfeil.org/wordpress/?p=868#comment-106 OK. Changed the term to 'Verilog HDL'. OK. Changed the term to ‘Verilog HDL’.

]]> By: belymt http://blog.spitzenpfeil.org/wordpress/2009/02/10/simulating-a-quadrature-decoder-with-ltspice-and-what-has-become-of-it/#comment-105 belymt Wed, 11 Feb 2009 09:45:40 +0000 http://blog.spitzenpfeil.org/wordpress/?p=868#comment-105 That code is Verilog, not VHDL. That code is Verilog, not VHDL.

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