It consists of user data, user components distribution, storage, file storage, user parameters by the user program area.
1. User data structure
User data structure is divided into three main categories:
First class is a bit of data. Second class is character data. Third class for words mixed with bit
2. Logic elements
(1) enter relay (X0 ~ X177) PLC input is received from an external switch signals window. Input of the FX2 relays up to a maximum of 128 points, use the octal numbers, and not program driven.
(2) the output relays (Y0 ~ Y177) output terminal of the PLC is to the output signal of the external load window. FX2 relay output can be up to 128, and the number to octal. Drive must be enforced by the output relay of the external load.
(3) auxiliary relay (m)
① General auxiliary relay M0 ~ M499 (500 points)
② power maintaining M500 ~ M1023 auxiliary relay (524)
③ M8000 ~ special auxiliary relays M8255 (256 points)
(4) element (s)
In stepping sequential control system programming status symbol in s is an important software component. It with the latter stepping sequential control instruction of STL in combination. There are four types:
Initial state S0 ~ S9 (10 points) back to zero–S10 ~ S19 (10 points)
The S20, ~ S499 (480) keep the S500 ~ S899 (400 points)
(5) alarm system (s) used as alarm status symbol: S900 ~ S999 (100 points). Part of the condition element can be used as an external fault diagnostic output.
(6) the pointer (P/I)
① branch instruction pointer P0 ~ P63 (64 points)
② break, using the pointer, I0–~ I8 – (9 points)
(7) the timer (t) (Word, bit)
① Timer actions and components
Inside the PLC, the timer is based on cumulative timing clock pulse, clock pulse 1ms, 10ms, 100ms, the time when the meter reaches the set value, the output contact action.
Timer component, and set values and actions is as follows:
• Timer (T0 ~ T245)
T0 ~ 100ms timer T199 (200 points)
Setting value 0.1 ~ 3276.7 seconds
T200 ~ 10ms timer T245 (46 points)
Set value of 0.01 to 327.67 seconds
(B) integrating timer (T246 ~ T255)
II the timing and accuracy of contact
From driving timer coil to contacts action, timing accuracy of contact generally represents available:
(8) counter (c) (Word, bit)
① internal signal counter
Internal signal counter when a scan is performed on the internal components (such as x, y, m, s, t, and c), the counter counts the number of signals.
• Increased 16 bit counters
There are two types of 16 bit binary counter increases:
General: C0 ~ C99 (100 points)
Power outages remain: C100 ~ C199 (100 points)
Their set values between K1 ~ K32767
• 32 bit bidirectional counter
Increase/decrease of two 32 bit counters:
Universal counter C200 ~ C219 (20 points)
Keep the counter C220 ~ C234 (15 points)
The set value is–2147483648 ~ +2147483647, counting direction determined by the special auxiliary relay M8200 ~ M8234. Special auxiliary relay switch on (set to 1) for reduction count when, otherwise count increases.
II high speed counter
C235 to C255 (21 points) is a high speed counter, but they share the same 6 high speed counter on PLC inputs (X0 ~ X5). Selection of high speed counter is not arbitrary, it depends on the type and speed of the counter you want to enter the Terminal. Counter types is as follows:
1 no start/reset terminals C235 ~ C240
1/start/reset terminals C241 ~ C245
2–phase bi-directional C246 ~ C250
2–phase A-B–phase C251 ~ C255
Figure 6-16 high speed counter
(9) the data register (d) (Word)
Programmable controller for analog control, position control,
Work requires a lot of data, it registers the storage parameters and data.
① General data register D0 ~ D199 (200 points)
If no other data are written, have been written to the data does not change. However, the PLC status by running (RUN) → stop (STOP), all data is cleared.
② power outage data register D200 ~ D511 (312 points)
As above, unless rewritten, otherwise the data will not be lost. Whether the power is switched on or not, PLC running or not, its content does not change. Two PLC for point-to-point communication, the D490 ~ D509 is used as a communication operation.
③ a special data register D8000 ~ D8255 (256 points)
The PLC data register for monitoring operation of various components in use. Its content in the power is switched on (ON), writes an initialization value (all cleared, and arranged by the system ROM write initialization values).
④ file registers D1000 ~ D2999 (2000)
File register is actually a kind of special data registers, used to store large amounts of data, such as data collection, statistical calculations, multiple set of control parameters and so on.
• Indexing registers (V/Z) (Word)
Indexing registers in a role similar to the z-80 index registers, IX, and IY, is commonly used to modify the element number of the soft component. V and z are 16 bit data register.
PLC ONE 