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Author :
Wichit
Sirichote
Introduction
If you
need
more
code
space
for your
application,
particularly
for
developing
89Cxx
projects
with C
language,
the
Easy-Downloader
V2.0 is
the
answer.
It's
suitable
and
cheap
which
anyone
can
build
easily.
This
version
is
capable
of
writing
intel-HEX
file to
a
89C51(4kB),
89C52(8kB)
and
89C55(20kB).
After
compiling
the
source
file in
Assembly
or C
then
download
the hex
file to
the chip
directly
by using
A:\>ez2
myfirst(.hex),
say.
Hardware
Figure 1
shows
the
circuit
diagram
of
Easy-Downloader
V2.0.
The
89C51
with
ez52.hex
receives
a 9600
baud
serial
data
from PC
and
generates
the
appropriated
signal
applying
to the
ZIF
socket.
P0 is
for
bi-directional
data
transferring.
P1
provides
A0-A7,
P2.0-P2.6
for
A8-A14.
Look at
A14, our
software
uses
P2.6,
while
ATMEL
uses
P3.0
instead.
Programming
mode
selection
is done
by P3.4
to P3.7.
See in
ez52.c
for
details.
The
programming
voltage
shown a
bit
different
from
version
1.1, Vpp
pin
needs
only +5V
and +12V
and
simply
activated
by P3.3.
The
clock
input
pin X1
of the
ZIF
socket
is
derived
from X2
without
buffering.
I have
tested,
no
problem
so far.
Click
here for
more
detail &
source
code |
