DayTronic System 10 - 12 Setup of Logic Bits and Logic Ports; 12.a Sourcing of Logic Bits

12 SETUP OF LOGIC BITS AND LOGIC PORTS
12.a “SOURCING” OF LOGIC BITS
Your system’s 1000 internal LOGIC BITS are numbered from “Bit No. 0”
through “Bit No. 999.” Before it can be used, a given bit must be assigned a
logic source. This source will continuously tell the bit what logic state it is to
assume at any time: “1” or “0.” The way a bit is “sourced” also determines
whether or not it will latch on being set to “Logic 1.” A “latched” bit must be
released (as explained in Section 13) before it can again be set.
To show you how the
LOGIC SOURCE (SRC) command works, we will have
you assign a source of “LATCHING LIMIT LOGIC” to a presently unused sys-
tem bit. In Section 13, this bit will be used to observe the limit behavior of your
“live” analog input Channel No. x as its transducer load is varied.
If your system has an optional
Model 10AIO-16 Universal Logic I/O Card,
you will use the
SRC command in the following section to designate which of
the 10AIO-16’s I/O ports are to be Logic
Input Ports and which are to be Logic
Output Ports.
Before you set any logic sources, however, you must learn to use the
SET BIT
(BIT)
command to set and read system logic-bit states.
1. You may disable the EEPROM Write Protect function if you want to, since it
need not be enabled for the “WRITE” form of the BIT command to work.
2. First enter from the keyboard a “READ” command of
BIT 3 [CR]
The present logic state of Bit No. 3 will be displayed as either “3, 1” or “3,
0.”
3. Use the
Step key as you did in Section 7 to display a sequential range of
existing bit states.
4. Now enter a “WRITE” command of
BIT 898 = 1 [CR]
(We are here assuming that Bit No. 898 is not presently involved in any of
your system’s preconfigured logic activities—channel “limit logic,” “Exe-
cute” functions, etc. Just to be safe, however, you might want to check
your “System 10 Data Sheet.”)
5. Verify that Bit No. 898 has been properly “set” by commanding
BIT 898 [CR]
An answer of “898, 1” should be displayed.
6. “Reset” Bit No. 898 to “Logic 0” by commanding
BIT 898 = 0 [CR]
7. You will now assign a logic source of “LATCHING LIMIT LOGIC” to Bit No.
898. Make sure the EEPROM Write Protect function is enabled, and enter
from the keyboard a command of
SRC 898 = LIM, LAT [CR]
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SETUP OF LOGIC BITS AND LOGIC PORTS
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