ADS-14221, PPT2 User Manual
October, 2016
21 of 85
5.0 Command Descriptions (alphabetical order)
COMMAND CODE
COMMAND DESCRIPTION
A= Data
String
A
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
No After
(4)
Both
Yes No Yes
(9)
No
DETAILS:
The
A=
data string command can be used to store and retrieve up to eight characters in the EEPROM. This
command must have 1 to 8 characters immediately following the ‘=’ character. The message is terminated with
the <cr> (ENTER key) character. If this string is stored in EEPROM with the SP=ALL command, it will remain in
the PPT2 even after the power is turned off. Example uses include dates for maintenance checks, over/under
range pressure or temperature values, or key pressure readings specific to application. (Default:
A=
<empty>)
NOTE:
EXAMPLES:
Inquiry: *dd
A=
Action:
*dd
WE
EEPROM Store: *dd
WE
*ddA=
Your_msg
*dd
SP=ALL
Your_msg
must have 1 to 8 characters immediately following the ‘=’ character. The message is
terminated with the <cr> character. The legal characters for
Your_msg
include all
characters between the ‘space’ (SP) and lower case ‘z’ inclusive, except the ‘*’, in
standard ASCII. Other characters outside this range are replaced with the “space”
character. (see Appendix B for the ASCII table)
DIFFERENCES FROM LEGACY PPT:
The A= command will now work with a *ddWE=RAM continuous write enable is active. The SP=ALL command is
now required before the value is written to EEPROM.
The PPT stored a parity bit for each pair of ASCII characters stored in the 8 character A= register. This is not
required for the PPT2.
The PPT response is always 8 characters with trailing spaces if required. The PPT2 responds only with the
characters stored.