©
National Instruments Corporation
8-1
8
Counters
USB-621
x
devices have two general-p
u
rpose 32-bit co
u
nter/timers and
one freq
u
ency generator, as shown in Fig
u
re 8-1. The general-p
u
rpose
co
u
nter/timers can be
u
sed for many meas
u
rement and p
u
lse generation
applications.
Figure 8-1.
USB-621
x
Counters
Co
u
nter 0
Co
u
nter 0
S
o
u
rce (Co
u
nter 0 Time
bas
e)
Co
u
nter 0 A
u
x
Co
u
nter 0 HW Arm
Co
u
nter 0 A
Co
u
nter 0 B (Co
u
nter 0 Up_Down)
Co
u
nter 0 Z
Co
u
nter 0 G
a
te
Co
u
nter 0 Intern
a
l O
u
tp
u
t
Co
u
nter 0 TC
Inp
u
t
S
election M
u
xe
s
Freq
u
ency Gener
a
tor
Freq
u
ency O
u
tp
u
t Time
bas
e Freq
O
u
t
Inp
u
t
S
election M
u
xe
s
Co
u
nter 1
Co
u
nter 1
S
o
u
rce (Co
u
nter 1 Time
bas
e)
Co
u
nter 1 A
u
x
Co
u
nter 1 HW Arm
Co
u
nter 1 A
Co
u
nter 1 B (Co
u
nter 1 Up_Down)
Co
u
nter 1 Z
Co
u
nter 1 G
a
te
Co
u
nter 0 Intern
a
l O
u
tp
u
t
Co
u
nter 0 TC
Inp
u
t
S
election M
u
xe
s
