22 channel x, 23 channel x, 1 channel x – Spectrum Controls 1769sc-HART Modules User Manual
Page 63: Command value, 2 unlatch process high alarms uh0 to uh3 (word 4)
Chapter 6: Module Data, Status, and Configuration
User’s Manual 0300217-03 Rev. A
6-11
6.3.22 Channel X
1
HART Slot Variables 0 & 1 (Words 34, 36, 38, 40)
This word defines HART slot variables 0 and 1 for the selected channel. The first byte
defines slot variable 0 and the second defines slot variable 1. The variable is defined as a
hexadecimal value between 0 and FF.
The HART slot variable is a floating point value that represents a device specific variable
defined by the manufacturer for the connected HART field device. This is an optional
configuration setting and is not supported by all HART field devices.
For more information regarding slot variables, refer to Section 7.2.
6.3.23 Channel X
1
HART Slot Variables 2 & 3 (Words 35, 37, 39, 41)
This word defines HART slot variables 2 and 3 for the selected channel. The first byte
defines slot variable 2 and the second defines slot variable 3.
The HART slot variable is a floating point value that represents a device specific variable
defined by the manufacturer for the connected HART field device. This is an optional
configuration setting and is not supported by all HART field devices.
For more information regarding slot variables, refer to Section 7.2.
Section 6.4
Output Data File
The output data file is used to command the analog signal for each channel as well as
controlling features which include, clearing process alarms, suspending HART
acquisition, and managing HART messages to and from HART field devices. The data
table structure is shown in the table below.
Table 6-7 (Output Data File)
W o rd /Bit
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
1
2
3
4
HS 3 HS 2 HS 1 HS 0
UL3 UH3 UL2 UH2 UL1 UH1 UL0 UH0
5
6
7
8..27
28..49
Res erved
Channel 0 Com m and V alue
Channel 1 Com m and V alue
Channel 2 Com m and V alue
Channel 3 Com m and V alue
Res erved
M es s age Reques t B uffer
P ac k et Jus t S c anned
M es s age M as ter Control
M es s age Reques t S iz e
6.4.1 Channel X
1
Command Value
The command value is used to control the analog output signal for each channel. The
command value is entered in engineering units defined by the channel’s selected data
format and output type. Refer to section 6.3.13 for more details regarding data format
and output type.
6.4.2 Unlatch Process High Alarms UH0 to UH3 (Word 4)
UH0 through UH3 will unlatch the high process alarms for channels 0 through 3
respectively. Refer to section 6.3.12 for more information regarding setting the alarm
latch function. To unlatch the high process alarm on a given channel, set the unlatch bit
to 1.
Note: Setting the unlatch process alarm bit will not clear the alarm latch if the
conditions that generated the alarm are still present.
1
Where X is the channel number (0 to 3)