100/180 mm PAPERLESS GRAPHIC RECORDER: USER GUIDE
HA028910
Issue 13 Sep 16
User Guide
Page 166
4.3.16 MASTER COMMS (Cont.)
READING DIGITAL VALUES
Digital values can either be the open/closed status of a discrete input, or it can be a status string show-
ing, for example Instrument Status, if ‘User Defi ned’ is selected as Parameter Type,
OPEN/CLOSED STRINGS
The text strings for the open and closed statuses of a digital input channel can be read by ‘Enabling’ the
Digital checkbox for the relevant slave and Channel number. The strings returned will be those entered
in the slave channel’s confi guration.
The default values are representations of an open switch (for Open) and a closed switch (for Closed). Fig-
ure 4.3.16h shows these two states.
Figure 4.3.16h Default Open/Closed depictions
STATUS BITS
This allows the user to view the value of a bit in a status word such as Instrument Status, Channels in
Group etc. The relevant Register is accessed by entering its decimal number into the Register fi eld which
appears when ‘User Defi ned’ is selected as Parameter.
Example
Figure 4.3.16i, below shows a master channel confi guration page which causes a message* to be sent to
allgroups if the memory device inserted in a slave recorder is full. Open / closed strings are also entered
as Disk OK and DiskFull respectively, so that if this channel is included in a group, then whichever of these
legends is appropriate will be displayed in the channel faceplate.
* Note: The message string is entered as a part of Message Confi guration as described in
section
4.3.8
.
From the recorder’s documentation, Instrument Status is held at register number 22. As can be seen
from table 4.3.16b, disk full status is reported by bit 4.
Open String
Closed String
Table 4.3.16b Instrument status (Register 22)
0
Not used
Always zero
1
1
Not used
Always zero
2
2
Not used
Always zero
4
3
Card/Disk.
0 = Inserted
1 = Missing
8
4
Card/Disk
0 = Not full
1 = Full
16
5
Not used
Always zero
32
6
Not used
Always zero
64
7
Channel status.
0 = No failures 1 = Channel failure 128
Bit
Item being tested
Status
Value
