Mighty Microcontrollers
Dateline: 07/05/00 Once again, your are choosing hardware
base for your new robot - as usual, it should combine small size, low
power consuption and computational abilities of modern Pentiums and Athlons
with the signal processing proficiency of discrete circuits. You already
heard about microcontrollers, highly integrated subclass of the microprocessor
family that can fulfill your expectations. However, guided by
modern enterprise IT principles, you refuse to develop closed, proprietary
architectures aimed at restricted sets of tasks. At the same time,
you don't want to invest large amount of both money and time to learn
all about new programming languages, development environments and exotic
hardware devices. We already described BASIC Stamp and BasicX , microcontrollers that can
be programmed in various dialects of Basic. However, things have changed quite
a bit during the last year: now we have even more powerful microcontrollers
that can be programmed in Basic or Java, so you can jump right in while
using previous programming experience. OOPic is an acronym for
Object-Oriented Programmable Integrate Circuit . It became quite popular
lately, allowing users to be more creative and productive by providing
an Object-oriented language model designed to interact with the electrical
hardware components. You start designing your hardware interface in software
by creating objects and setting their properties to define their behavior and
interaction with hardware (11 hardware objects are directly supported,
from 1-Bit Digital Input to the RC Servo Controller). These objects also
can be interconnected to form a Virtual Circuit .
A Virtual Circuit is a function in an OOPic that appears to be a
physical discrete electronic circuit, but is actually the OOPic operating system
emulating the functionality of the circuit. Virtual Circuits are created
by linking together a set of objects in the same methodology as you would
physically link together a set of electronic components. Once created, each
individual part of the circuit can be manipulated or evaluated by the program.
Object-oriented notation and event-driven approach are fully supported, and
the exchange of data between several OOPics is accomplished by a Virtual Circuit
that utilizes oDDELink (Dynamic Data Exchange) objects to transfer data over an
I2C Network (standard created by Philips Corporation). The OOPic Basic syntax is
compatible with Microsoft�s Visual Basic, making it really familiar to a wide
range of developers. There are even more good news: the OOPic C syntax and Java
syntax are currently being developed, so you'll have an opportunity to choose
between some of the most popular programming languages. Another, even more powerful microcontroller, comes from Wilke Technology GmbH. Their BASIC Tiger
is offering up to 6 MB of memory (!) and is ideal to use for
long-time stand-alone sampling or outputting longer sequences of graphic or
sound. This product line enable the use of video clips with voice and sound
output, graphics symbol display, images, drawings and virtual instruments,
resulting in more informative and comprehensible applications. LCDs with 128 x
64 pixels to 240 x 128 pixels connect directly to the Tigers' expansion bus.
The TINY Tiger
is very similar to the larger BASIC Tiger, offering almost the same features.
With its smaller chassis and up to 2.5 MB of memory it is used wherever space is
limited but still much memory and I/O lines are required for your application.
The newest member of the family, Tiny Tiger Economy, offers up to 1 MB of memory with
characteristics very similar to the more powerful Tigers.
Going further on a complexity scale, integration of process control and enterprise applications still remains a dream of many software developers. Java promises to bridge the gap between industrial control applications and standard business solutions. Sun started it all with its picoJavacore, suited for consumer electronic products that run Java applications (like digital set-top boxes, Internet TVs, Internet screen phones and automotive communications devices). The combination of the small size of the processor core and the performance gained from direct execution of Java code instructions means that smaller, higher performance devices such as cellular phones, TV set top boxes and other information appliances can be rapidly developed and brought to market. However, just a few companies offering "Java silicon" currently target hard real-time embedded applications. Now separate efforts under way at aJile Systems Inc., and Advancel Logic Corp. indicate alternative architectural approaches. aJile, a spun out of Rockwell Collins, bases its work on the 20 years of experience with similar processor architectures. Their aJ100 processor features multiple Java virtual machines and an embedded real-time operating system on the chip, designed to efficiently accelerate Java real-time runtime environments. The aJ-PC104 CPU is a single board CPU based on the existing JEM2 processor from Rockwell Collins that can be used as a Java processor module in a PC/104 stack or as a stand-alone single board Java computer. Advancel's is currently working on a dual-language processor that runs both the C programming language as well as Java natively.