ADS-14221, PPT2 User Manual
October, 2016
22 of 85
COMMAND CODE
COMMAND DESCRIPTION
AN Analog
Range
Setting
Action
Directing
Sequential
Response
with (90-99)
address
Input or
Output Type
Requires
Write Enable
Terminates
Continuous
Commands
Can Write to
EEPROM
Can Write to DAC
Yes
Before
Both
Yes (6)
No
Yes (9)
Yes
DETAILS:
The
AN
command turns on and off the custom
AN
alog output setting of the DAC. The analog range setting is
established with the
H=
and
L=
commands. Analog window settings are established with the
O=
and
W=
commands. When
AN
is
ON
, the customized settings are activated; when
OFF
, the factory default range of 0V to
5V is active. When custom
H=
and
L=
range settings are used, the resolution of the analog signal will be
reduced. For example, the full 5 volt range has a 15+ bit resolution. A range reduction to 2.5 volts will result in a
7+ bit resolution. Ranges between these two values would result in a resolution between 7+ and 15+ bits. The
use of analog window limits
O=
and
W=
can increase the volts/pressure resolution of the analog signal.
(Default:
AN=ON
)
NOTE:
Regardless of
AN
setting,
DX
and
DZ
settings are always active.
AN
command settings affect the analog output
only when
DA=A|B|C|D|E|F|G|M|M|R
. When
DA=V
the analog output is disabled (floating).
EXAMPLES:
Inquiry: *dd
AN
Action:
*dd
WE
EEPROM
Store:
*dd
WE
*dd
AN={ON
|
OFF
|
ON-
|
OFF-}
*dd
SP=ALL
ON
The analog output will adjust to the high and low limits (
H=
,
L=
) and the offset and
window limits (
O=
,
W=
). The highest pressure produces the high (
H=
) output voltage
and the lowest pressure produces the low (
L=
) voltage.
OFF
The analog output will set to 5 volts for the FS pressure (
F=
) and to 0 volts for zero
pressure - or negative FS pressure for differential.
ON-
Same function as
ON
, but output scale is reversed. i.e. The highest pressure produces
the low (
L=
) output voltage and the lowest pressure produces the high (
H=
) voltage.
OFF-
The analog output will set to 0 volts for the FS pressure (
F=
) and to 5 volts for zero
pressure - or negative FS pressure for differential.
DIFFERENCES FROM LEGACY PPT:
No difference from PPT implementation.
