KROHNE UFC 500 HART - Manual (Page 8)

HARTô Smart Communications Protocol
UFC500 Command Specification Rev: 2.0 Release Date: 9 Jun 2001
© 2001 KROHNE Mefltechnik D-47058 Duisburg Page 8
4. Additional Response Code Information
FIRST BYTE
4.1 Busy
Bit #5
The Busy Response Code is implemented for every command despite of its type (Read, Write or Command) and is
reported if an EEPROM-burning operation was activated (by some preceeding command of Write or Command type),
that is not yet concluded. The burning time cannot exceed 700 msec (the worst case), though normally is carried out
within TT0 interval (256 ms). A confirming response is made before the execution begins (but after validation of a
request data).
4.2 Transmitter-Specific Command Error
Response code value 6 for UFC500 implies that device is controllled directly via its keypad and is reserved for further
transmitter revisions. For the present revision this response is overriden by the Busy Response Code: when the
instrument is operated manually, HART application layer doesnít get control.
SECOND BYTE
All the flags that are implemented by transmitter, are listed below.
4.3 Configuration Changed
Bit #6
This flag is set whenever any configuration parameter is changed either via bus request or by direct instrument control
via keypad.
4.4 More Status Available
Bit #4
The instrument status can be masked while handling this flag. The mask depends of the value of variable
ErrorMessageControl (refer to Command #156). Bit #4 is set when the logical ìorî of the status and mask is nonzero.
Note, that the bytes responded on Command #48, are not masked.
4.5 Primary Variable Analog Output Fixed
Bit #3
This flag is set under two conditions: when the function of current output is switched ìOffî or when fixed current mode
is entered via bus request (Command #66).
4.6 Primary Variable Analog Output Saturated
Bit #2
Handled as specified.