User Manual

Chapter 4: Module Data, Status, and Configuration
U ser 's M a n u a l 0 300 21 5- 03 R ev. A
6-15
Sec t ion 6.5
Output Data File
The output data file allows yo u to co ntrol module features such as, clearing process
alarms, suspending HART acquisition, and allows managing of HART messages to and
from HART field devices. The data table structure is shown in the table below.
Table 6-9 (Output Da t a File)
Word/Bit
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0 HS3 HS2 HS1 HS0 UL3 UH3 UL2 UH2 UL1 UH1 UL0 UH0
1
2
3
4..23
24 ..4 5 Rese rve d
Reserved
M es sag e Re qu est Buff er
Packet Just Sca nned
Me ssage Master Control
Me ss age Re ques t Si z e
6.5.1 Unlatch Process High Alarms UH0 to UH3 (Word 0)
UH0 through UH3 will u nlatch the high process alarms for channels 0 through 3
respectively. Refer to section Filter Frequency and General Settings (Words 2, 8, 14, 20)
for more information regardin g setting the alarm latch function. To unlatch the high
process alarm on a given cha nnel, set the unlatch bit to 1.
Note: Setting the unlatch process a larm bit will not clear the alarm latch if the
conditions tha t generated the alarm are still present.
Note: It is up to the user to keep the unlatch bit set until v erification that the p ro cess
alarm bit has cleared. When the process alarm bit has cleared the user can then clear
the unlatch process alarm bit.
Note: The module will not latch the high p ro cess alarm if a transition fro m “no alarm
condition” to “alarm cond ition” occurs while the u nlatch high p ro cess alarm bit is set.
6.5.2 Unlatch Process Low Alarms UL0 to UL3 (Word 0)
UL0 through UL3 will unlatch the low process alarms for channels 0 through 3
respectively. Refer to section Filter Frequency and General Settings (Words 2, 8, 14, 20)
for more information regarding setting the alarm latch fu ncti on. To unlatch the low
process alarm on a given channel, set the associated unlatch alarm bit to 1.
Note: Setting the unlatch process a larm bit will not clear the alarm latch if the
conditions tha t generated the alarm are still present.
Note: It is up to the user to keep the unlatch bit set until v erification that the p ro cess
alarm bit has cleared. When the process alarm bit has cleared the user can then clear
the unlatch process alarm bit.
Note: The module will not latch the low process alarm if a transition fro m “no alarm
condition” to “alarm condition” occurs wh ile the unlatch l ow process alarm b it is set.
6.5.3 Hart Suspend HS0 to HS3 (Word 0)
HS0 to HS3 are used to suspend all H ART acquisition, except Pass-through messages, o n
channels 0 through 3 respectively. To suspend HART acquisition, set the as sociated
channel suspend bit to 1. Normal HART acquisition will resume when the bit is cleared.
6.5.4 Packet Just Scanned (Word 1)
When demultiplexing HART data fro m the module, this output word can be used to
speed up the acquisition process by overriding the automatic 500ms acquisition delay