Issue
163 February 2004
The
Growth of the Atmel AVR Family
PLUG
IT IN
Now,
it’s time to make the magic happen. Both demo PCBs have
a DE-9F for serial communication. Of course, using the
XPort and AVR microcontroller in a design does not require
any RS-232 converters or connectors; but, jury-rigging
the demo boards requires a cable. Try and find a DE-9M-to-DE-9M
cable when you need one. Forget it. Fiddling around
in the junk box I found two crimp-on DE-9Ms and a short
piece of ribbon cable. I plugged it in and, voila, no
magic. Doh! This needs to be a null modem cable.
After
the physical connections are completed correctly, things
started to look up. Using my browser, I contacted the
XPort and got a pop-up comment on installing the Java
environment. Then up came the thermostat layout that
I showed you in my “Global XPortation” column (Circuit
Cellar 162).
This
time, however, the XPort talks to the AVR microcontroller,
and the information displayed on the LCD is reflected
on the display in the browser window (see Photo 2).
I can click on the browser’s buttons and the changes
are sent back to the thermostat. Yes.
|
(Click
here to enlarge)
|
Photo
2—I placed a small front panel over the LCD on the
STK502 adapter. The ZIF socket on the left holds
the ATmega169 device. Black dots on the front panel
indicate the positioning of push button switches.
The physical switches on the STK500 demo board are
actually along the bottom edge of the PCB just out
of view. |
EXPANDING
UNIVERSE
From
the standard eight-pin ATiny controllers to the ATmega
with high-density in-system programmable flash memory,
there’s an AVR solution tailored to meet your most specific
needs. And note that both the instruction set and architecture
are the same for all AVR products. So, when your code
increases, you can easily and quickly port to a larger
device. AVR comes three ways: as a standard package
product, an application-specific standard product, and
an ASIC core integrated into a System-on-a-Chip solution.
You
can depend on Atmel to continue expanding its collection
of successful AVR products. The RISC core’s single-cycle
instructions result in serious code efficiency. The
AVR’s flash memory technology provides in-circuit programming
thanks to a separate “boot flash.”
You
can smile, knowing that Atmel is constantly improving
its suite of program and system development tools. It’s
the kind of support that ends up saving you precious
design time. After all, if your design time decreases,
then you’ve earned a little free time. And what better
way to make use of it than to lie in a hammock and watch
the grass (or weeds) grow.
