B-2
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Appendix B
Timing Diagrams
Figure B-1.
M Series Analog Input Timing Engine
The following signals are used in Figure B-1 and in the following sections:
•
Terminal
—Refers to any device terminal, such as PFI or RTSI. These terminals are used
as inputs and as outputs for signals.
•
_i
—Refers to any internal signal available to the analog input timing engine for use. In the
case of signals coming from an external terminal, this is the signal after is been through the
first input buffer. _i also can refer to other internal signals such as internal timebases or
signals coming from other blocks.
•
POUT
—Refers to any output signal right before it is driven to an output terminal.
•
Convert Clock Timebase and Sync Convert Clock Timebase
—Convert Clock Timebase
is the source signal used to generate the signal that will actually cause the ADC to do a
conversion (p_AI_Convert). This signal can be an internal or external timebase that is
divided by the SI2 counter, or can be an external Convert Clock signal. Sync Convert Clock
Timebase is a signal related to Convert Clock Timebase that is used to synchronize external
signals before they are used by circuits running from Convert Clock Timebase.
•
Sample Clock Timebase and Sync Sample Clock Timebase
—Sample Clock Timebase
is the source for the SI counter and can be used to generate the sample timing. Each Sample
Clock in turn triggers the generation of one or more converts. This signal can be an internal
or external timebase. Sync Sample Clock Timebase is a signal related to Sample Clock
Timebase that is used to synchronize external signals before they are used by circuits
running from Sample Clock Timebase.
S
t
a
rt Trigger
Termin
a
l
S
elected Reference Trigger
Reference Trigger
Termin
a
l
Termin
a
l
S
elected
Sa
mple Clock
Termin
a
l
Termin
a
l
Termin
a
l
S
elected
S
t
a
rt Trigger
RT
S
I
Termin
a
l
Termin
a
l
Termin
a
l
S
elected P
aus
e Trigger
S
I
Co
u
nter
Block
S
I2
Co
u
nter
Block
S
I_TC
Sa
mple Clock Time
bas
e
S
ync
Sa
mple Clock Time
bas
e
Convert Clock Time
bas
e
S
I
S
t
a
rt
P
aus
e Trigger
S
I2_TC
p_AI_Convert
S
t
a
rt
1
(
a
nd Other Co
u
nter
s
,
a
nd
Su
ch of Timer Core)
POUT
POUT
POUT
POUT
POUT
POUT
S
ync Convert Clock Time
bas
e
_i
_i
_i
_i
_i
_i
_i
_i
Summary of Contents for PCI-6281
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