Re: Few questions on embedded stuff

From: Ben Bradley (ben_nospam_bradley_at_mindspring.com)
Date: 06/26/04 

Date: Fri, 25 Jun 2004 19:57:33 -0400

On Thu, 24 Jun 2004 21:04:31 GMT, zalzon <zalzonishappy@zalll.com>
wrote:

>Hi,
> How much do you embedded guys need to know about analog circuit design?
>I asked one guy and he said most embedded engineers know little about
>analog circuitry.

   Perhaps not "most" but certainly too many. These are apparently the
embedded people who come out of computer science. There are still
people like me who have an electronics/EE background (both digital and
analog) who ended up working with embedded processors, and can do more
of the project (sorry, I don't do marketing).

>Usually they look at application notes on how to build
>sample circuits. Is this true?

   As someone else said, this is always a good idea, regardless of
one's knowledge level. But still, it helps to have an analog
background
   I attended National's mos recent Bob Pease tour, and one section
was on National's op-amps and ISTR some slides (at least in the book,
they may have just mentioned them in the presentation) on op-amp
configurations and gain calculations. To knowledgable analog guys,
that's about equivalent to a nand gate's truth table.

>Also what real-time OS do most of u guys use? Is it mostly used on single
>board computers?

   Most of my designs have used a "heartbeat" interrupt as well as one
or two other interrupts, and I hang many of the tasks on the heartbeat
interrupt. I've written all the code the processor runs. I'm sure I
have a big hole in my resume from lack of RTOS experience.

>Finally, why are there so many different vendors selling single board
>computers.

   You may have also noticed a wide range of prices, processor power,
electrical power the board takes, various peripherals and other
features available. etc. You can prototype a wrist watch with a MSP430
or Atmel "Butterfly" board, but it probably won't run Linux. There
are a huge number of different applications under the word "embedded"
and the vendors are just selling what people buy.

>Do they all custom build their stuff, is there no standard?

   There are a "few" standards, but lots of stuff is "non-standard."

>Thanks