EmbeddedRelated.com

Jack Crenshaw (@JackCrens)

Author, ESD column "Programmer's Toolbox" Book "Math Toolkit for Real-Time Programming" Tutorial series "Let's Build a Compiler" Manager, Comp-Sultants, Inc. Company developed embedded systems based on 4040 and 8080, ca. 1975. Designed & developed embedded systems based on discrete chips, 1972-76. Chief Software Engineer, Heathkit, 1978. President, Crenshaw Associates, developing embedded systems 1994. Staff Scientist, Invivo Inc., developing systems and software for patient monitors; specifically blood O2, CO2, and anesthetic gas subsystems, 1995-9 Languages included Fortran, Pascal, C, C++, Python, 10 assembly languages. Very active in early days of hobby/personal computers. Electronics hobbyist since 1956, digital hobbyist since 1965.

Re: Choice of microcontroller for a project

Reply posted 5 years ago (05/11/2019)
I second (or third) the motion for Arduino. Not only are they cheap, but there's a ton of user-created software libraries for every possible I/O device you can name,...

Re: Regarding a specific microcontroller

Reply posted 5 years ago (04/30/2019)
I'm more than a little surprised that no one has given you the obvious answer: GET AN ARDUINO UNO.They're cheap ... under $12 on Amazon, and under $5 for Arduino...

Re: DIY hi-fi

Reply posted 5 years ago (03/22/2019)
Ok, this changes EVERYTHING. If I understand you correctly, the transformer was buzzing even with no load connected to it. Then the circuit worked for a couple of...

Re: DIY hi-fi

Reply posted 5 years ago (03/22/2019)
I'm a little surprised that the design requires so many different voltages. I've never heard of a design needing two different HV supplies. I'm also confused that...

Re: Stack - interrupt, function call?

Reply posted 5 years ago (01/05/2019)
Kocsonya has reminded me that the 68000 used two stacks, the User stack and the Supervisor stack.  This let folks writing operating systems separate user space...

Re: Stack - interrupt, function call?

Reply posted 5 years ago (01/05/2019)
Ok, thanks for the reminder. I must admit, I had forgotten about the User vs. Supervisor mode.  Thanks for reminding me.One of the things I really admired about...

Re: Stack - interrupt, function call?

Reply posted 5 years ago (01/04/2019)
I'm a simple man, so I'm going to give you a simple answer: THERE IS ONLY ONE STACK.I see that other folks disagree, and that's OK. Apparently there are "odd" CPUs...

Re: Low level programming

Reply posted 5 years ago (12/05/2018)
Jim, thanks so much for the extra details.  I see that you & I have been down many of the same roads.I'm still a little confused about the dates, though. Are...

Re: Low level programming

Reply posted 5 years ago (12/05/2018)
Bob11 nailed it!!!Jack

Re: Low level programming

Reply posted 5 years ago (12/03/2018)
Jim, like you I'm a "seasoned" computer guy.  Like you, I started writing code long before C was available.  But I'm puzzled by your comment that you had to write...

Re: Low level programming

Reply posted 5 years ago (12/03/2018)
Hi, ani!  I've read your inquiry and the replies, and have a couple of bits of advice. Some of this is going to rub other folks the wrong way, and I apologize in...
Yep, it used to be almost the model for a "good" Fortran program, back in the day.  And you're right: The excuse is usually performance. Thankfully, computer scientists...
I agree with bamos.  You can't create a C++ class in C, but you can do the next best thing by putting the data item and the functions that operate on it in a separate...

Re: Fundamental frequency of a Guitar string

Reply posted 6 years ago (06/29/2018)
Donvoth, you said "The harmonics are an integral part of the original signal."That sounds wrong to me. I thought you were building a tuner to let you tune the guitar...

Re: Fundamental frequency of a Guitar string

Reply posted 6 years ago (06/29/2018)
If you are getting such strong second harmonics, it could be because the signal itself is highly nonlinear.  Have you looked at the signal on a scope?Also, most...

Re: Wanting to get back into Embedded Systems

Reply posted 6 years ago (05/11/2018)
No, the Arduino IDE _DOES_ use C++.  It just doesn't look like it because the general structure -- the setup() and loop() functions. plus most of the built-in library...

Re: Wanting to get back into Embedded Systems

Reply posted 6 years ago (05/10/2018)
Hi. I'm in pretty much the same situation. Was programming 8080's -- and even 4040's -- back in 1975, for use in embedded systems. I did a _LOT_ of software and...

Re: Which FPGA kit to start with in 2018?

Reply posted 6 years ago (03/26/2018)
Can't claim to be an expert; Like you I'm just getting into FPGAs, and for the same reasons.  But I've ordered an Elbert V2, which has the Xilinx Spartan 3A chip:https://www.amazon.com/Numato-Lab-Elbert-V2-Develo...It's...
I guess I'll lose this competition because I'm not going to try to answer the question directly, but talk in more general terms.First of all, I reject any notion...

Re: PID controller help

Reply posted 6 years ago (01/19/2018)
Outstanding!! Sounds like you're on your way to a cure.Jack

Re: PID controller help

Reply posted 6 years ago (01/19/2018)
First of all, what you're seeing is not "sporadic oscillation," but noise, pure and simple. It seems to me you need to get the signals calmed down before you start...

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