Mitsubishi Electronics FX1S manual STL Programming

3. STL Programming			3-1
3.1	What is STL, SFC And IEC1131 Part 3?		3-1
3.2	How STL Operates		3-2
3.2.1		Each step is a program	3-2
3.3	How To Start And End An STL Program		3-3
3.3.1		Embedded STL programs	3-3
3.3.2		Activating new states	3-3
3.3.3		Terminating an STL Program	3-4
3.4	Moving Between STL Steps		3-5
3.4.1		Using SET to drive an STL coil	3-5
3.4.2		Using OUT to drive an STL coil	3-6
3.5	Rules and Techniques For STL programs		3-7
3.5.1		Basic Notes On The Behavior Of STL programs	3-7
3.5.2		Single Signal Step Control	3-9
3.6	Restrictions Of Some Instructions When Used With STL		3-10
3.7	Using STL To Select The Most Appropriate Program		3-11
3.8	Using STL To Activate Multiple Flows Simultaneously		3-12
3.9	General Rules For Successful STL Branching		3-14
3.10	General Precautions When Using The FX-PCS/AT-EE Software		3-15
3.11	Programming Examples		3-16
3.11.1 A Simple STL Flow			3-16
3.11.2 A Selective Branch/ First State Merge Example Program			3-18
3.12	Advanced STL Use		3-20

4. Devices in Detail			4-1
4.1	Inputs		4-1
4.2	Outputs		4-2
4.3	Auxiliary Relays		4-3
4.3.1		General Stable State Auxiliary Relays	4-3
4.3.2		Battery Backed/ Latched Auxiliary Relays	4-4
4.3.3		Special Diagnostic Auxiliary Relays	4-5
4.3.4		Special Single Operation Pulse Relays	4-5
4.4	State Relays		4-6
4.4.1		General Stable State - State Relays	4-6
4.4.2		Battery Backed/ Latched State Relays	4-7
4.4.3		STL Step Relays	4-8
4.4.4		Annunciator Flags	4-9
4.5	Pointers		4-10
4.6	Interrupt Pointers		4-11
4.6.1		Input Interrupts	4-12
4.6.2		Timer Interrupts	4-12
4.6.3		Disabling Individual Interrupts	4-13
4.6.4		Counter Interrupts	4-13
4.7	Constant K		4-14
4.8	Constant H		4-14
4.9	Timers		4-15
4.9.1		General timer operation	4-16
4.9.2		Selectable Timers	4-16
4.9.3		Retentive Timers	4-17
4.9.4		Timers Used in Interrupt and ‘CALL’ Subroutines	4-18
4.9.5		Timer Accuracy	4-18
4.10 Counters			4-19
4.10.1 General/ Latched 16bit UP Counters			4-20
4.10.2 General/ Latched 32bit Bi-directional Counters			4-21

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