The TASM Language Reference Manual Version 1.1 - Synrc

More documents

Recommendations

Info

TASM Example 2 Light Switch Version 2 ENVIRONMENT: USER-DEFINED VALUES: light_status := {ON, OFF}; switch_status := {UP, DOWN}; RESOURCES: memory := [0, 16000]; //bytes processor := [0, 100]; //percentage VARIABLES: light_status light := OFF; switch_status switch := DOWN; -------------------------------- MAIN MACHINE: MONITORED VARIABLES: switch; CONTROLLED VARIABLES: light; RULES: R1: Turn On t := [4, 10]; memory := 200; processor := 25; if light = OFF and switch = UP then light := ON; R2: Turn Off t := 6; memory := 100; processor := 15; if light = ON and switch = DOWN then light := OFF; R3: Else else then skip; 16
• T RU 1 = (5, ((memory, 200), (processor, 25)), (light, ON)) • T RS 1 = T RS 0 ◦ T RU 1 = (5, ((memory, 200), (processor, 25)), ((light, ON), (switch, UP ))) For all times gt in the open interval (0, 5), the state TRS is (gt, ((memory, 200), (processor, 25)), S 0 ). The same logic can be applied to the other two sample runs. 2.5 Hierarchical Composition So far, we have dealt only with basic ASM specifications, that is, specifications that contain only a single abstract state machine. These restrictions were sufficient because the examples have been simple. However, for more complex systems, structuring mechanisms are required to partition large specifications into smaller ones. The partitioning enables bottom-up and top-down construction of specifications and creates opportunities for reuse. We introduce the concept of hierarchical composition by introducing different types of abstract state machines - main ASM, function ASM, and sub ASM. A main ASM is a ”top-level” machine, that corresponds to a single thread of execution. A main ASM cannot be used by other ASMs. A basic ASM specification is thus a specification that contains a single main ASM. The two other types of machines, function ASMs and sub ASMs are auxiliary ASMs that enable hierarchical composition. The composition mechanisms included in the TASM language are based on the XASM language [1]. In the XASM language, an ASM can use other ASMs in rule declarations in two different ways - as a sub ASM or as a function ASM. A sub ASM is a machine that is used to structure specifications hierarchically. A sub ASM has the same syntax as a main ASM except for the designation of sub ASM. It yields an update set which is merged with the update set of the parent machine. A function ASM is a simple ASM that takes a set of inputs and returns a single value as output, similarly to a function in programming languages. These two concepts enable abstraction of specifications by hiding details inside of auxiliary machines. The definition of a sub ASM is similar to the previous definition of machine ASM: SASM = 〈n, MV, CV, R〉 Where n is the machine name, unique in the specification, and other tuple members have the same definition as mentioned in previous sections. The execution and termination semantics of a sub ASM are different than those of a main ASM. When a sub ASM is invoked, one of its rules is selected, it yields a timed update set, and it terminates. The use of the next keyword is forbidden in both sub and function ASMs. The definition of a function ASM is slightly different. Instead of specifying monitored and controlled variables, a function ASM specifies the number and types of the inputs and the type of the output: Where: F ASM = 〈n, IV, OV, R〉 17
Page 1 and 2: The TASM Language Reference Manual
Page 3 and 4: Contents 1 Introduction 5 2 The Lan
Page 5 and 6: List of Figures 2.1 Hierarchical co
Page 7 and 8: Chapter 1 Introduction This documen
Page 9 and 10: Chapter 2 The Language The Timed Ab
Page 11 and 12: 2.2 Basic Definitions The term spec
Page 13 and 14: TASM Example 1 Light Switch Version
Page 15 and 16: The keyword next, used with time sp
Page 17: of resource usage for the step. If
Page 21 and 22: The composition of resources also f
Page 23 and 24: T RU ret = T RU 1 ⊕ ( (T RU 2 ⊕
Page 25 and 26: • T RS 0 = (0, ((memory, 0)), ((l
Page 27 and 28: RC 1 ⊙ RC 2 = (rc 11 , . . . , rc
Page 29 and 30: The example is further extended to
Page 31 and 32: TASM Example 8 Fan Main Machine Def
Page 33 and 34: Table 2.1: Special Operators Operat
Page 35 and 36: main machine templates. The concept
Page 37 and 38: Chapter 3 Syntax This chapter descr
Page 39 and 40: Table 3.1: Reserved Keywords Keywor
Page 41 and 42: Table 3.2: Operators Operator Signa
Page 43 and 44: TASMUCaseLetter > ::= ′ A ′ |
Page 45 and 46: 3.2.2 Project < TASMProjectDef > ::
Page 47 and 48: 3.2.5 Syntax Common to all Machine
Page 49 and 50: 3.2.8 Function Machine < TASMFTempl
Page 51 and 52: Table 3.3: XML Tags for Top Level S
Page 53 and 54: env types rsrcs vars vname tname *
Page 55 and 56: sys confs * conf name desc viname v
Page 57 and 58: XML Example 4 XML for a list of tem
Page 59 and 60: cons cbody cparams body * cparam cp
Page 61 and 62: XML Example 5 XML for main ASM temp
Page 63 and 64: Table 3.11: XML Syntax Tree for Fun
Page 65 and 66: 3.4.2 Typing All variables are stat
Page 67 and 68: Table 4.1: Operator Precedence Oper
Page 69 and 70:
4.2.5 Rules The desugaring of the r
Page 71 and 72:
is used to sum up all of the resour
Page 73:
[10] Y. Gurevich. Evolving Algebras
show all

The TASM Language Reference Manual Version 1.1 - Synrc

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?