Chapter 11 Flashcards Preview

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Flashcards in Chapter 11 Deck (27):
1

To a predetermined step by step process that accomplishes a specific task.

Sequencing

2

Frequently used for reversing the direction of AC and DC motors, or for controlling multispeed motors with two to four speed settings

Drum Switches

3

An output instruction that uses a file or an array to control various output devices

Sequencer output (SQO)

4

An input instruction that compares bits from an input file or array to corresponding bits from a source address

Sequencer input (SQI)

5

An output instruction that compares bits from an input source file to corresponding bits from data words in a sequence file. If all pairs of bits are the same then a bit in the control register is set to 1

Sequencer compare (SQC)

6

An output instruction that functions like a word to file or file to file transfer

Sequencer load (SQL)

7

In the starting address for the registers in the sequencer file and you must use the indexed file indicator (#) for this address

File

8

The coed or bit pattern through which the sequencer instruction moves source data to the destination address

Mask

9

The address of the input word or file for an SQC from which the instruction obtains data for comparison to its sequencer file

Source

10

The address of the output word or file for an SQO to which the instruction move data from its sequencer file

Destination

11

The address that contains parameters with control information for the instruction and discrete output to indicate sequencer instruction

Control

12

The found bit (FD) is only used for the SQC instruction

Bit 8

13

The error bit (ER) indicates a negative position value or negative or zero length value

Bit 11

14

The done bit (DN) is set by the SQO or SQC instruction after it has operated on the last work in the sequencer file

Bit 13

15

The enable bit (EN) is true when the rung goes form false to true and is used to indicate that SQO and SQC instruction is enabled to active.

Bit 15

16

The number of steps of the sequencer file starting at position 1

Length

17

The word location or step in the sequencer file from/to which the instruction moves data

Position

18

SQO

Sequencer output

19

SQI

Sequencer input

20

SQC

Sequencer Compare

21

SQL

Sequencer Load

22

Bit 8

FD
found bit

23

Bit 11

ER
error bit

24

Bit 13

DN
done bit

25

Bit 15

EN
enable bit

26

SQO instruction operation during the first scan

o If the rung is true at the time of the first scan and the position parameter is 0, then the data in the memory location at position 0 is transferred through the mask to the destination register and the position pointer is incremented by 1.

o If the rung is false at the time of the first scan and the position parameter is 0, then the data in the memory location at position 0 is NOT transferred to the destination register and the position pointer is NOT incremented.

27

SQO instruction operation after the first scan

o When the rung has a false to true transition the position pointer is incremented by 1 and the data in the memory location at the new position is moved through the mask to the destination file.

o If the position memory location data changes while the rung is true, the SQO continues to update the destination file on every scan.

o When the rung goes false the output is no longer updated, and the SQO instruction waits for the next false to true rung transition.