Spectrum Controls 1769sc-HART Modules - Manual (Page 76)

Compact IO™ Isolated HART Analog Input Module
User's Manual 0300215-03 Rev. A
7-8
Table 7-5 (HART Packet 4)
Tag Name Data Type Style Description
If4ih0Packet4 Packet4[4,1] NA Two dimensional array containing packet
4 data for all 4 channels.
If4ih0Packet4[X,0].HartChannelID INT BIN Bits 0 to 3: Channel number (0 – 3).
Bit 4: Searching/Initializing HART device
Bit 5: HART communication failure or
device not found
Bit 6: Pass-through message pending (ready)
Bit 7: Unused (0)
Bits 8 to 10: Packet ID
Bit 11 through 15: Unused
If4ih0Packet4[X,0].Date SINT[3] DEC Stored date in the field device
If4ih0Packet4[X,0].FinalAssemblyNumber SINT[3] DEC The final assembly number is used for
identifying the materials and electronics that
co mprise the field device.
If4ih0Packet4[X,0].ExtendedStatus SINT[24] DEC The extended status returned by HART
co mmand 48
If4ih0Packet4[X,0].Pad SINT[3] DEC Pad 32 bit alignment
1
X represent s the module channel number (0 t o 3)
Note: Not all of the HART data that is returned by the process outlined in Figure 7-3
(Auto Acquisition Flow) gets passed to the packets. In order to access the data that is
not passed to the packets, you must execute the appropriate HART message using the
pass-through command, which will be discussed later in this chapter.
The ladder determines which packet to copy the data to by monitoring the state of bits 0,
1, 2 and 8, 9, 10, found in the first two bytes of the Local:X:I.HartData tag. Bits 0, 1, 2
determine the current channel being scanned and bits 8, 9, and 10 determine the packet
number. The ladder example, shown in Figure 7-4, performs this operation.