User Manual

Compact IO™ Isolated HART Analog Input Module
U ser 's M a n u a l 0 300 21 5- 03 R ev. A
7-8
Table 7-5 (HART Packet 4)
Tag Name
Data Type
Style
De scription
If 4ih0 Packe t4 Pa cket 4[4,1] NA Two dim en sional array containin g packe t
4 data for all 4 channels.
If4ih0 Packet4 [X,0].Ha rtChanne lID IN T B IN
B its 0 t o 3: C hanne l numbe r (0 – 3).
Bit 4: Se arc hing/Initializing HART device
B it 5: HAR T c omm unic at ion f ail ur e or
de vi c e not found
B it 6: Pa ss- through m ess age pending (re ady)
B it 7: Unused (0)
B its 8 t o 10: P acke t ID
B it 11 t hrough 15: Unused
If4ih0 Packet4 [X,0].Da te SINT[3 ] DEC
S tor ed dat e i n the fiel d devi ce
If4ih0Packet4[X,0].Final AssemblyNumber SINT[3] DEC The fina l assembl y numbe r is us ed for
identif ying the mat er ia ls and ele c tronics that
co mprise the field device.
If4ih0 Packet4 [X,0].Exten de dS tatus SINT[2 4] DEC The e xte nded sta tus re turned by HART
co mm and 48
If4ih0 Packet4 [X,0].Pad SINT[3] DEC
Pa d 32 bit ali gnment
1
X repr ese nt s th e m o dul e ch ann el n um b er (0 t o 3 )
Note: Not all of the HART data that is returned by the process outlined in Figure 7-3
(Auto Acquisitio n Flow) gets passed to the packe ts. In order to access the data that is
not passed to the packets, you must execute the appropriate HART message using the
pass-thro ugh command, which will be discussed later in this chapter.
The ladder determines whic h packet to co p y the data to b y 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.