Download Development and testing of the digital control system for the

most significant byte.
in this case the least significant byte first, then the
COUNTER 2 binary
Bits
Once
COUNTER 2.
select
The counters
square wave which
are loaded with
is
The read/write
numbers
must be loaded with a value
manner
to
to
Mode
produce the desired output.
M2=X, Ml =
1
and
M0=1
wave
is
loaded
select
COUNTER
to the
3
bits
to
complete, the
is
be
10
MUX
milliseconds
accomplished by setting up the card for
into
COUNTER 2.
and
1
wave whose
COUNTER
2.
BASE ADDRESS + 15
of
sheet,
RW1
and
To
the
RWO,
COUNTER CONTROL
which from the 8254 data sheet produces
begins sequencing through the
desired channels scanning one channel per rising edge.
numbers
COUNTER CONTROL
8254 data
The
first.
mode
1].
output.
initialization
was established
three create a 10
3 produces a square
loaded into
is
With Reference
which byte
the desired square
Once
XXI 1X1 10
a binary
COUNTER CONTROL.
select as before
previously
enable the 8254 to operate in the desired
frequency depends on the values loaded in
rate
make mode
that
the registers are loaded with values, then the
mode
bits are as
the desired sampling rate for the control laws' [Ref
register
select this
select
1XXXX is loaded into the COUNTER CONTROL register.
SC0 = 1 and SCI =0
described.
ms
101
To
COUNTERS
The output of
1
and 2
[Ref
The
1].
control laws' sampling
This
sampling rate
"EXTERNAL TRIGGER". Then
that
COUNTER
2
39
create
is
a
10
ms
is
loading
square wave out of
then be fed into pin 25 of the card to