Choosing a good starter microcontroller

[Mike]

I want to start experimenting with microcontrollers, and don't know where to start. On page 22 in the january issure of N&V, there is an ad for Kronos Robotics. They are selling a Athena microcontroller for only $7, and the carrier board for $5.95. The complete educational package is $50, which i could afford with christmas money. I just want to use buttons to control things like relays, leds, etc. just to figure out how they work. I asked a while ago about an audio switcher, and think that this might even work good for that. it would switch 4 relays and leds by the press of a button, and another button would pull down or release a relay for mute mode. two more buttons would control a digital volume control. Would this chip work for that also?<p>Is the Athena a good microcontroller to begin with? <p>Thanks for the help, Mike

[L. Daniel Rosa]

Mike, kudos on getting the uC bug! I'm getting into it too. Before committing to it, look into how much support there is for it. PICs appear to be the most popular among hobbyists around here, and Atmel and Motorola are vying for second place. It certainly gets a bit easier if you can copy somebody else's code.<p>Yes, I think the Athena will be able to do most or all of the tasks you mentioned. The problem I see is that the Athena has space for 256 instructions- granted they are "high level", but this is a trade-off.<p>Which comes into your second question. The Athena appears to be a PIC (16F648A, '819, '87, or '88) with an on-the-fly interpreter that reads the flash ram for the "high level instructions". This gives you something more familiar to work with if you've never done machine code. The disadvantage is that it becomes top heavy with features you may not need for a particular application, and the total operation is slower. It looks leaner and meaner than the "stamp", and costs less too. For what it's worth, you may be able to get the software for the Athena (or something similar) and program a PIC yourself, and come out ahead by a few dollars per uC.

[Lin Farquhar]

Have a look at rev-ed.co.uk Revolution Education.
They sell several levels of bootstrapped PICs programmable in BASIC. The cost of the PICaxe chip is little more than the native PIC. The programming suite is a free download and the programming hardware consists of a D9 plug and two resistors.
Rgds, LF

[Mike]

So, should I start with a PIC instead of the Athena? What will I need to program and use the PIC?<p>Thanks, Mike

[wd5gnr]

There are PIC tutorials all over the Web. Mine are at http://tutor.al-williams.com (also CPLD and other tutorials).

[L. Daniel Rosa]

I won't dictate what you should start with. Within a given range there's not much one brand of uC can do that another can't as long as they both have the I/O ports to support it. It's just a matter of code. <p>However, I have seen more free support for the PICs than I've seen for all the others combined. That's not to say that it isn't there, but that I haven't looked very hard and as such didn't find much.<p>As for the programming software, there's something at http://www.ic-prog.com/ that has been recommended by one of the merchants selling some programming hardware. One such item is at http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... egory=4661 .<p>The programmer is pretty simple though. It uses some tricks in software to reduce the parts count. But at twelve and a half bucks it's hard to justify making one.

[samsmiles]

Im avr atmel fan big time. Its cheap and easy to use. I made my own programmer etc. All on low student budget. There is lots of great web pages with avr atmel related data, projects etc and some good books. Freeware software is also available for development. AVR is very popular in academic env. <p>Thats my 5 cents.
Sam