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Hello I'm interested in getting into microcontrollers. I'm a computer tech but I don’t know a lot about programming. I do have some electronics training and I’m comfortable with basic circuits.
I have been looking at the nuts volts magazine and it seams the 2 big manufactures are Parallax and Basic Micro (Atom)
So what one is good and will be good for the future but is good to start with? I read that there are different types of languages that you can program with. Java basic or Pbasic? Assembly? Anyway I want to invest time into this but don't want to learn a language that will be obsolete in say 2 years. Also if anyone knows a good chip to start with it would be appreciated. I will probably start playing with some small robot projects but would like to learn to develop them for machine control. Currently at work I use Schneider Electric PLC’s and program them using a program called PL7. I use Ladder logic mainly to program them. We also use special cards for PID and heater control. Also for motion control for servos etc. Are there any type of add-ons chips for this type microcontroller? For motion etc.?<p>Thanks for your time I appreciate any info you can provide I don’t want to start off on the wrong foot!<p>Mark
[email protected]
Nova Scotia, Canada

Just to be a little picky (pun sort of intended),
<edited due to error in statement.><p>Java may make your programs much bigger than necessary, though I haven't actually researched that aspect.<p>I would definitely look at learning assembler for the Pic only 35 instructions for the 16F series -even if you decide to code in with an HLL. Personally while in the learning phase, if you are looking at a basic cross compiler then I'd look at one that produces a true ASM/.LST file as from this you can often see why your program ain't doing what it oughter. With ASM it is true you need to learn a new variant if for example you decided later on to use a different manufacturers controller. In which case programming in C or harder to get Pascal would be the way to go- very little re-writing.<p>For Pic's I'd look at experimenting with either the 16F628 or 16F870 in the base range or even jump straight into the new 18F range with the 18F252, slightly more instructions but you don't have to worry about banks.<p>For excellant support BasicMicro is the way to go.<p>Colin<p>[ October 13, 2002: Message edited by: bodgy ]</p>

I suggest you go right ahead and buy Microchip
Picstart Plus from Dig-Key, (about 100 bucks) and jump right in. There are about 35 assembly language codes. Each takes one clock tick unless a sequence change is made, requiring two ticks.
The asembler is sort of strange but easily understood. There are books that come with the programmer and a PIC16F84 to play with. Stay away from high level languages with a microcontroller.
I have an old programmer I am giving away. See my post in Robotics.
This is good stuff. Jump right in.

Go for microengineering PicBasic Pro. Excellent compiler, with good support and easy to learn. While your at it Microcode Studio for windows based programming, and Microchip MPLab w/Picstart. Basic stamps are good, but going right to PICs will pay for itself within a few projects.

I started out with Microchip's PicStart programmer, and it works rather well for assembly projects. I've done a fair amount of programming (20 or 30 projects each) in c and assembly on the PIC, and have found that Microchip's dev tools are somewhat unstable at times and that the chips aren't as powerful as some others for the same money. The are only 35 instructions in the whole set, making the learning curve in assembly very shallow, but also leaving some extra capabilities out.<p>More recently I've developed with Atmel's AVR line. These chips have a slightly different, and much more powerful architecture. There are 70ish instructions, hardware pointers, hardware multiply, 32-register ALU (as opposed to 1 on the PIC), and many of the details in the modules are better.<p>As an example, when using PulseWidthModulation on the PIC to drive a flyback SMPS's primary FET, the PIC allowed missed pulses to occur in the output. The problem comes because the pulse is active low and this means the FET was left on for the entire PWM period. The fet normally draws up to 3 Amps, but when a missed pulse occured, it spiked up as high as 30A because it was left on for much too long.
The AVRs have this problem solved by only loading the new compare value when the PWM counter is at 0 (i.e. not changing the value it's looking for until just before it needs to start looking), which avoids changing the value to one you've just passed over and mising it.
Many other little issues exist in the PICs that are taken care of in AVRs.

bodgy is wrong Basic Micro’s "Basic Atom" is based on the PIC16F876 for the 24 and 28 pin module and the PIC16F877 for the 40 pin module the soon to be released Atom Pro is based on Hitachi microcontroller.<p>The Atom is way above the basic stamp in abilities and usability allowing for in circuit debugging and a far superior word list. With the basic stamps if they have more than 2k of program space you are still limited to 2k programs you van switch banks but you can’t pass variable. With the Basic Atom you have 8k of program space and you can use all of it. I have seen an older version of microengineering PicBasic Pro and Basic Micro’s Mbasic Pro is much more user friendly.<p>If you are looking to start out with PIC’s I recommend Basic Micro products they are high quality and the support is great.<p>Craig

Oops my error :p <p>Sorry about that - I saw the Hitachi addy and thought that it was current as far as the top of the range Atom was concerned.<p>Colin<p>[ October 13, 2002: Message edited by: bodgy ]</p>

Microcontrollers are not good computers. Do not try to make a comprohensive program with one. Use them for simple functions, one for each function and connect them with cables to make your big program.
Use the cheapest, simplest microcontroller you can find.

Thanks for all your input It is greatly apprechiated! I think I will jump right in with a PIC. Looks like BasicMicro Atom might be a good place to start. I think my employer will support me on this so hopefully they will pay for the things i need to get started. I will also research some other lines of pic suppliers also like picstart.
Thanks again for helping the newbie!<p>Mark
Nova Scotia, Canada

Gosh I need a job - I'll emigrate to Canada let me at your employer. <p>colin