IMO i3C Lite, Руководство пользователя

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CHAPTER 14: REGISTERS
14.1 Register Definitions
When programming the
i ³C Lite, data is stored in memory that is segmented into different types. This
memory in the controller is referred to as registers. Different groups of registers are defined as either
bits or words (16 bits). Multiple registers can usually be used to handle larger storage requirements.
For example, 16 single-bit registers can be used to store a word, or two 16-bit registers can be used
to store a 32-bit value.
Table 14.1 - Types of Registers found in the i³C Lite
%I Digital Input
Single-bit input registers. Typically, an external switch is connected to the
registers.
%Q Digital Output
Single-bit output registers. Typically, these bits are connected to an actuator,
indicator light or other physical outputs.
%AI Analog Input
16-bit input registers used to gather analog input data such as voltages,
temperatures, and speed settings coming from an attached device.
%AQ Analog Output
16-bit output registers used to send analog information such a voltages, levels or
speed settings to an attached device.
%M Retentive Bit Retentive single-bit registers.
%T Temporary Bit Non-retentive single-bit registers.
%R General Purpose Register Retentive 16-bit registers.
%D Display Bit
These are digital flags used to control the displaying of screens on a unit which
can display a screen. If the bit is SET, the screen is displayed.
%K Key Bit
Single-bit flags used to give the programmer direct access to any front panel
keys appearing on a unit.
%S System Bit Single-bit bit coils predefined for system use.
%SR System Register 16-bit registers predefined for system use.
14.2 Useful %S and %SR registers
Table 14.2 – Common %S Register Definitions
Register Name Description
%S1 FST_SCN Indicate First Scan
%S2 NET_OK Network is OK
%S3 T_10MS 10mS timebase
%S4 T_100MS 100mS timebase
%S5 T_1SEC 1 second timebase
%S6 IO_OK I/O is OK
%S7 ALW_ON Always ON
%S8 ALW_OFF Always OFF
%S9 PAUSING_SCN Pause 'n Load soon
%S10 RESUMED_SCN Pause 'n load done
%S11 FORCE I/O being forced
%S12 FORCE_EN Forcing is enabled
%S13 NET_IO_OK Network I/O is OK