Specifications
ProLinx Communication Gateways, Inc. 22
HART Master Protocol Drive Manual
August 17, 2004
Command
Parameter
Range
Description
specified by the Maximum Register parameter under the [MODBUS
MASTER] section.
Poll Interval 0 to 65535 This parameter specifies the minimum interval to execute continuous
commands (Enable code of 1). The parameter is entered in units of
seconds. Therefore, if a value of 10 is entered for a command, the
command will execute no more frequently than every 10 seconds.
Word Count -1 to 125
This parameter specifies the number of words from the floating point data
returned by a HART command that will be placed on the Virtual Database.
If this parameter is 0 no data will be written to the Database. If this
parameter is –1 then all the floating point data will be written in the integer
block of data.
Special care should be taken with this number, because is a word count
and a floating point value is 2 words long. For example if you execute a
HART command 3 which takes 5 floating point values from the device, you
should place a word count of 10 words.
Swap Code 0,1,2,3 This parameter is used to define if the data received from the HART slave
is to be ordered differently than received from the slave device. This
parameter is helpful when dealing with floating-point or other multi-register
values, as there is no standard method of storage of these data types in
slave devices. This parameter can be set to order the register data
received in an order useful by other applications. The table below defines
the values and their associated operations:
Swap Code
Description
0
None – No Change is made in the byte ordering
1
Words – The words are swapped
2
Words & Bytes – The words are swapped then the bytes in each word are
swapped
3
Bytes – The bytes in each word are swapped
Short
Address
1 to 15
This parameter is used to specify the HART slave node address on the
network to be considered. Values of 1 to 15 are permitted. If the device to
be addressed only accepts long address, then the parameter “Use Long”
should be selected so the module can ask for the long address with the
short one and then execute the command.
Function
Code
0 to 255
This parameter is used to specify the HART function to be executed. Any
HART function can be executed, even device specific ones, but only
supported commands will return formatted data and classified in floating
point data and integer data.
Int. DB
Address
0 to 3999 This field specifies the internal database register where the integer or
packed ASCII string values returned by the command will be placed.
If the Floating Point Word Count parameter is “–1”, then all the data
returned by the HART command will be placed in this address without any
formatting.
Register addresses specified for commands must reside in the range
specified by the Maximum Register parameter under the [MODBUS
MASTER] section.
Word Count 0 to 125
This parameter specifies the number of words from the integer or packed
ASCII string data returned by a HART command that will be placed on the
Virtual Database. If this parameter is “0”, no data will be written to the
Database.
Swap Code 0,1,2,3 This parameter is used to define if the data received from the HART slave
is to be ordered differently than received from the slave device. Its format
is the same that the specified for the Floating Point Data Swap Code (see
above).