DayTronic System 10 - 13 Limit Setup

3. Select three bits from the bit group you specified in the above BSL com-
mand. Let’s call them Bit Nos. b
1
, b
2
, and b
3
. If, for example, you specified
Bit Group No. 3, then b
1
, b
2
, and b
3
could be any three numbers from 32
through 47.
4. Enter from the keyboard these three
SRC commands:
SRC b
1
= INP, NON [CR]
SRC b
2
= INP, NON [CR]
SRC b
3
= INP, NON [CR]
Since you have thus designated the three Logic I/O Ports corresponding
to Bit Nos. b
1
, b
2
, and b
3
to be INPUT ports, the individual logic state of
each of these three ports will now directly and continuously control the
state of its corresponding system bit
(in a NONLATCHING mode). All
other ports are still automatically assumed to be OUTPUT ports.
The indi-
vidual logic state of each OUTPUT port will be directly and continuously
controlled by the state of its corresponding system bit
.
13 LIMIT SETUP
In this section, you will learn how to
• define HIGH and LOW limit values for a given data channel, using the
LOW
LIMIT (LOL)
and HIGH LIMIT (HIL) commands
• set the VISUAL EFFECTS to occur for the CRT display of a given data
channel, depending on its current limit status, using the
“LESS THAN”
STATUS (VLT)
, “BETWEEN” STATUS (VBT), and “GREATER THAN”
STATUS (VGT)
commands
•create a BIT-STATE FIELD for CRT display of a given logic bit
• arrange for a data channel’s HIGH-LIMIT violation to set a given system
logic bit, using the
“GREATER THAN” LOGIC (LGT) command
• arrange for a LOW-LIMIT violation of the same channel to set another
logic bit, using the
“LESS THAN” LOGIC (LLT) command
•release a “latched” bit, using the
RELEASE (RLS) command
• cancel a channel’s existing “GREATER THAN” and “LESS THAN” LOGIC,
using the
LGT and LLT commands
a. To set the LOW LIMIT value for Channel No. x (the channel you calibrated
in Section 10, above), make sure the EEPROM Write Protect function is
enabled, and enter from the keyboard a command of
LOL x = L [CR]
where “x” is the channel number and “L” is the desired low-limit value
expressed to the required precision. In this case, it should be about 20%
of the channel’s full-scale reading. For example, if you’re using a 50-
pound load cell as source transducer for Channel No. x, which was cali-
brated in Section 10 to read
tenths of a pound, then enter an “L” value of
“10.0.”
b. To set the HIGH LIMIT value for Channel No. x, enter a command of
HIL x = H [CR]
where “H” is the desired high-limit value expressed to the required preci-
sion. In this case, it should be about 80% of the channel’s full-scale read-
ing. If, again, you were using a 50-pound load cell for readings precise to
a tenth of a pound, then you would enter an “H” value of “40.0.”
B - 26
LIMIT SETUP
“O NTHE A IR ” (B-S IZED )