Newbie tackles ambitious project-Help me choose proc.&dev. tools.

Hi,

I'm new to the group and to the world of microcontrollers, but can find
my way around a variety of assembler languages. I am planning two
projects for this summer, and would be very grateful indeed if you
would suggest an AVR microcontroller, development hardware, and
software+tutorial materials for each.

Project 1: A two-color darkroom led lamp controller with timer.

Feature A: Color and luminosity control.
Device will have independent 2 banks, one blue, one green of high
intensity LEDs.
Each bank to be set at one of 10 luminosity levels using PWM.
Luminosity levels (Pulse width) in 2 lookup tables, one for each bank.

Feature B: Linear and Logarithmic timer functions. Timer for lamp can
be set linearly in minutes/seconds using rocker switch and
increased/decreased logarithmically (e.g.2x,4x,8x)
using a second rocker switch. Log base (i.e. 2, 1.41 etc) selectable
using a third rocker.

Feature C: LED display for luminosity level set. 4 digit LED display
for timer. 1 digit display for logartihmic base chosen (one of 7 from a
lookup table).


Project 2 is a similar timer/controller with more timing inputs and LED
displays, but the controlled item is a stepper motor for chemical
agitation.

So, where should I begin?

Which AVR chip is the most amenable to being programmed by a newbie,
and at the same time has some built in support for these various
functions (log increments, timer up, timer down, LED driver etc. etc).
Bare bones is ok.

What testing board should I use? What software?

My budget is $60 for the above chip+programmer/test board+software ,
max. (excluding the cost of controlled hardware such as the LEDs and
the input switches etc).


I'd be immensely grateful for any guidance. I know it will take the
summer, but I'm really looking forward to this.

 

You're into S&M are you ?

Why AVR ? Atmel also make '8051s', probably the world's most used uC ( for many
good reasons ).

Graham

 

I'd start with free winAVR GCC toolset and the Atmel butterfly. I have
both, but have never got around to using them

Personally I'd start of programming in C, and then delve into asm when
I need it.
But then I only use the 8051, in C, and for the most part it has
always been fast enough for me, and doing darkroom stuff is not really
going to strech any normal 8 bit micro


martin

 

Me to pretty much.

Absolutely right. Hardly any call for RISC architecture there ! And 8051s can
use 33MHz clocks now too. ~360 ns for a typical 2 cycle instruction IIRC.

Graham

 

I'll suggest a great value 8051 eval board for $25 instead.

http://cgi.ebay.com/8051-MCS51-MCS-...7623143318QQcategoryZ4661QQrdZ1QQcmdZViewItem

Graham

 

Morning Graham,
I'm looking at using a 8051 for mucking with AES digital audio stuff
(really), with a cirus decoder, plus some TTL, I'd considered using
the Alesis/wavefront AL3101 DSP,and the tools suck, but I'd still need
an 8051 to control it. I'm still stuck at 11.0592 MHz clock, cos I
can't be bothered to rework the baudrate timers


martin

 

And here's a programmer too from the same guy for $20 ! It'll program the Atmel flash 8051 parts like the 89S53. It does AVRs
too.
More info on this stuff here.
http://anyway.no-ip.org:8080/

Graham

 

Do tell more !

Yes. I used their optimistically named 'tools' on their reverb DSP chip. I briefly
trialled the 3101/2 tools too as I nearly selected one for an audio processor
project ( in the end I went the analogue route ). They do work as advertised of
course.

Duh ! I don't have it handy but I think I have the timer reload values somewhere
for a 12MHz crystal for most popular baud rates.

Graham

 

not yet

Did you try Bkasm? It looks rather useful, but unsupported, I couldnt
see how to get the delay ring buffer ( whatever it's called) set up in
Bkasm


martin

 

Pfftttt ! ;~ p

No. In fact I only just googled it to find out what you meant. Sounds interesting.

The Alesis, sorry Wavefront assembler is hardly actually *supported* anyway !

There's a ring buffer mode for the 3101 ? Wasn't aware. In the rev chip of course
that's the default.

Oh, check out the price of the 89S52 from Farnell btw.
http://uk.farnell.com/jsp/endecaSea...87c52&Nty=1&showImages=true&N=0&Ntk=gensearch

Graham

 

IIRC 1024 words, the pointer is auto incremented on each audio sample.

woohoo, cheap, must google for "8051 freelance programmers in India"


martin