[time-nuts] favorite microcontroller module?

Didier Juges didier at cox.net
Thu Feb 21 20:06:05 EST 2008


Most of my projects have a serial port and a standard comm interface. Once I
get that up and running, I use it for debugging.

That's the point where I start to breathe better too :-)

I have had my share of grief with emulators also. It was not enough that
they cost $1,000's and required these monster cables such that sometimes
they did not even fit on the target board... They had their own temperament.


On the other hand, emulator or not, I had to squeeze my brain a lot more
when things did not work. Now, I put a breakpoint or two, and in little
time, the problem is usually identified.

This is a case where I definitely do not miss the old days.

I also agree with you that decent C compilers and sufficient resources on
modern chips have made assembly mostly a thing of the past. Except for a
very recent project where I had to design a circuit that generates a number
of interlaced sync pulses with precise timing. I could have done it with a
PLD, but it was simpler to use a Silabs uC, with its built-in stable clock
at 25 MHz. Using assembly allowed me to keep timing to within the 40nS cycle
time. For what I wanted to do, the compiler generated more code, simply
because it was the wrong tool for the task. The Silabs solution was 1 chip,
instead of two for the PLD. Since I used another Silabs chip in the project,
it also simplified programming (same tool).

Didier

> -----Original Message-----
> From: time-nuts-bounces at febo.com 
> [mailto:time-nuts-bounces at febo.com] On Behalf Of Chuck Harris
> Sent: Thursday, February 21, 2008 9:37 AM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] favorite microcontroller module?
> 
> Hi Didier,
> .., I can use a pin that ordinarily
> >> would run an LED as a diagnostic port.
> > 
> > I had forgotten these tricks, which were the norm 20 years 
> ago when I 
> > was too lazy to pull the 6805 emulator.
> 
> It's sort of funny, 20 years ago, I was flush with emulators, 
> and used them
> for most of my development.   The had their place back then, 
> as my projects
> were spiraling out of control in terms of complexity.
> 
> Now, I just do PICS, and don't need such things.  I can debug 
> most effectively with either simple diagnostic messages, or a scope.
> 
> I don't miss how code that would work with the emulator 
> bombed without the emulator ... and vice versa.
> 
>   Now that I am used to the full debug
> > capability of the Silabs chips, which uses only the reset and one 
> > other pin on the smaller chips (the other pin being able to share 
> > debug and normal duty), I don't have to resort to tricks 
> like this :-) 
> > You get that capability even with their $18 USB based "development 
> > system" that's the size of a stick of gum.
> 
> PIC's will do the same thing.  I just haven't had the need to yet.
> 
> > 
> >> Many would say this is a religious issue, but I would disagree.
> >> The 6 and 8 pin PICS are simply awesome in what they can do in 
> >> virtually no space.  The tools are cheap, or free.  The PIC's are 
> >> cheap too.
> >>
> > 
> > No religion involved, I think the PIC line is unequalled 
> when it comes 
> > to the variations and features that are available in the small pin 
> > count packages. Silabs only has half a handful of chips in DIP 
> > packages (is two the same as half a handful?) but they have some 
> > pretty awesome parts in SM packages that are 3x3 mm or so 
> (they start 
> > at 11 pins, 10 + a tab), so if you do not do the soldering by hand, 
> > you can't complain that there is no room for a powerful uC.
> 
> True, they have made a number of wins.
> 
> > I am getting familiar with the AVR line simply because a 
> number of my 
> > friends use them and speak highly of the architecture, but 
> in general, 
> > I try to stay with open, multi-sourced architectures, so 
> the 8051 has 
> > a leg up on PICs and AVRs from the start. I made that decision when 
> > Motorola forced me out of the 68HC05, like so many others. 
> I have not 
> > regretted it. Motorola was not able to get me in the HC08, 
> even though they gave it a good try.
> 
> I tried to learn the HC10, but I could find no compelling 
> reason to learn yet another processor.
> 
> > was not going down that road again. Burn me once, shame on 
> you, burn 
> > me twice, shame on me (or is it: don't burn me again?)
> > 
> > The Silabs chips start at a couple of $, so they are out of 
> the sub-$1 
> > market for sure. That's fine with me, I don't mind paying 
> an extra $ 
> > for the features and convenience :-)
> > 
> > Like many things, uC are tools. The tool that you are the most 
> > comfortable with is often the best choice, for practical 
> reasons, even 
> > more so when you have to make a living out of it. For me, it's 
> > important to know that when I start a project, I can finish 
> it within 
> > schedule and within budget. My familiarity with the 8051 
> and many of 
> > its variants (and my favorite compiler, and the ton and a half of 
> > available code) gives me that capability, but as you 
> pointed out, it's 
> > not the only way. I understand you feel the same about the 
> PIC. That's perfectly OK.
> > 
> > Now, if you want an evening of fun, buy a Silabs toolstick 
> and a base 
> > adapter (about $28 + shipping from Mouser) and you have 
> everything you 
> > need (hardware and software, including demo version of the Keil C 
> > compiler) for a fun uC project. Please note the Keil C51 
> compiler can 
> > be replaced with the free and excellent SDCC compiler.
> 
> I have one around here someplace.  I was frustrated because I 
> couldn't get it
> to work under linux and wine.   CCS has a native linux 
> compiler, and their windows
> compiler works nicely under wine.  I am having some trouble 
> with Microchip's programmer under the current wine release, 
> but it has worked in the past, I'll get it working again.
> 
> > 
> > Here is an example of what you can do in an evening:
> > http://www.ko4bb.com/Test_Equipment/AFSignalGenerator/SigGen.html
> 
> Your server seems to be down right now.
> 
> -Chuck Harris
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com To unsubscribe, 
> go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
> 
> No virus found in this incoming message.
> Checked by AVG Free Edition. 
> Version: 7.5.516 / Virus Database: 269.20.9 - Release Date: 
> 2/20/2008 12:00 AM
>  
> 

No virus found in this outgoing message.
Checked by AVG Free Edition. 
Version: 7.5.516 / Virus Database: 269.20.9 - Release Date: 2/20/2008 12:00
AM
 




More information about the time-nuts mailing list