This circuit is intended to program AVR
controllers such as the AT90S1200 via the parallel port. The circuit is
extremely simple. IC1 provides buffering for the signals that travel
from the parallel port to the microcontroller and vice versa. This is
essentially everything that can be said about the circuit. The two
boxheaders (K2 and K3) have the ‘standard’ ISP (in system programming) pinout for the AVR
controllers. The manufacturer recommends these two pinouts in an
attempt to create a kind of standard for the in-circuit programming of AVR-controllers.
These connections can be found on many development boards for these
controllers. The software carries out the actual programming task.
It is therefore necessary to have a program (ATMEL AVR ISP), which is available as a free download from http://www.atmel.com. The construction of the circuit will have to made on standard prototype board, since we didn’t design a PCB
for this circuit. This should not present any difficulties considering
the small number of parts involved. We recommend that inexperienced
builders ﬁrst make a copy of the circuit and cross off each connection
on the schematic once it has been made on the board. This makes it easy
to check afterwards whether all connections have been made or not.
Author: P. G oossens
Copyright: Elektor Electronics