semi合集-English.pdf - 第2205页

SEMI E54.##-0705 © SEMI 2005 4 6.8.1 The Device shall com ply with A-LINK applicati on layer specificat ion for defi ning and addressing objects including f unctions deferred in lo wer layers as described above. 6.8.2 Us…

100%1 / 7923
SEMI E54.##-0705 © SEMI 2005 3
5.3.4 Device Profile — a kind of electric table to provide the characteristic features of a device including
configuration and capabilities.
5.3.5 Service Access Element — an addressable location in a device for the directing of service requests.
5.3.6 Data Exchange — a capability to communicate such data for a device as raw/processed sensed data and
variable settings.
5.3.7 Directive — a capability to instruct such basic functions to a device as reset or abort.
5.3.8 DP Facility — a capability to manage diagnostic matters.
5.3.9 Unite Inventory — a capability to realize and communicate the Device Profile.
5.3.10 Unite States — a capability to communicate state of a device.
6 Communication Protocol High Level Structure
6.1 In a typical remote I/O configuration, single master architectures are used to optimize response times. In
complicated applications, multi-master architectures are also possible. A-LINK uses the polling principle for
communication.
6.1.1 Message transfer is organized in cycles. A message cycle mainly consists of a request-frame followed by a
corresponding acknowledge/response-frame of the addressed station. An exception to this is the global-control
function for synchronization and coordination of several remote I/O stations.
6.1.2 A brief description of the A-LINK protocol as it relates to the ISO 7498 OSI model follows in the sections
below. For protocol efficiency, A-LINK does not define layers 3 to 7. However, since the OSI model specifies
Layer 7 as the interface between the Application Process and the communication stack, it is appropriate to discuss
several aspects of the A-LINK standard at this level.
NOTE 1: The information contained in this section is for reference only. It in no way represents specifications for A-LINK. See
related documentation for these specifications.
6.2 Physical Layer — Layer 1
6.2.1 The bottom Physical Layer is established by RS-485. See the A-LINK standard for more information for
detail.
6.3 Data Link Layer — Layer 2
6.3.1 Data Transfer
6.3.1.1 The Data Link Layer provides the functions for sending and receiving data over the network. Data Elements
are packaged, delivered, and checked. Acknowledgements, responses, retries, and timeouts are used to guard
against Line Protocol Errors (e.g., frame, overrun, and parity) and Transmission Protocol Errors (e.g., start and end
delimiters, frame check, frame length, and response times).
6.4 Network Layer — Layer 3
6.4.1 There is no distinct network layer.
6.5 Transport Layer — Layer 4
6.5.1 There is no distinct transport layer. Such functions as disassembling of message into transport unit and
reassembling for transportation are implemented in the Application Layer.
6.6 Session Layer — Layer 5
6.6.1 There is no distinct session layer.
6.7 Presentation Layer — Layer 6
6.7.1 There is no distinct presentation layer. Such functions as data representation conformance are implemented in
the Application Layer.
6.8 Application Layer — Layer 7
SEMI E54.##-0705 © SEMI 2005 4
6.8.1 The Device shall comply with A-LINK application layer specification for defining and addressing objects
including functions deferred in lower layers as described above.
6.8.2 User Interface (UI)
6.8.2.1 The UI provides the user with access to functionality of the A-LINK protocol as a part of application layer.
7 Required Object Types
7.1 This section describes a general mapping of the SEMI SAN Object Model to the A-LINK environment.
Component definitions are clarified and the mapping of Attributes, Services, and Behaviors are specified.
7.2 Object Model
7.2.1 The Object Model defined in the CDM is represented in the A-LINK NCS. Especially the DM, SAC, and
abstract or fundamental application objects are mapped.
7.2.2 The Application Objects associated with the SDM standards are mapped in A-LINK User Forum Public
Specification documents. §9 specifies the mapping of SDM Objects in A-LINK.
7.3 Component Mapping Summary
7.3.1 Table 1 provides a summary of the components of the CDM object model as they relate to the components of
A-LINK.
7.4 Objects
7.4.1 The required objects of the CDM are identified here. Additional objects that are contained in the SDM are
given identifiers in the Device Profile. §9 specifies additional mapping information.
7.4.2 Table 1 lists the Object Identifiers specified for use in protocol messages.
Table 1 Object Identifiers
Object Name A-LINK Class/Object ID CDM Object ID Tag CDM Attribute/Service ID Tag Prefix
Device Manager 1 DmI0 Dm
SAC 2 SacI0 Sac
Assembly 3 AsmIn Asm
Local Link 4 LnkIn Lnk
Sensor–AI 9 SenIn Sai
Sensor–EI 10 SenIn Sei
Sensor–BI 11 SenIn Sbi
Sensor–BI–TH 12 SenIn Sbith
Actuator–AO 17 ActIn Aao
Actuator–EO 18 ActIn Aeo
Actuator–BO 19 ActIn Abo
Controller 24 CntIn C
Application Objects >31 - -
7.5 Attributes
7.5.1 All attributes are accessible via Get_Attribute and Set_Attribute services defined in the sections below.
Attributes are also accessible via different A-LINK peculiar instructions which are additionally mapped in this
document based on attribute type.
7.5.1.1 The attributes of the DM object consists of distinctive information, states, and setups. Distinctive
information attributes are retrieved with the Unite Inventory. Inquiring state attributes are provided by getting status
data. Setup attributes are written by setting configuration data.
SEMI E54.##-0705 © SEMI 2005 5
7.5.1.2 The attributes of Application objects are divided into two types: Input/Output, settings, status and
Configuration. Input/Output attributes are acquired from or given through Data Exchange capability of A-LINK.
Configurable attributes can be retrieved with Unite Inventory capability.
7.5.1.3 See Table 2 for a list of DM attributes and their related alternative access instructions.
7.5.1.4 A-LINK Settings
7.5.1.4.1 Attributes related to general settings are accessed through Unite Inventory communication.
7.5.1.4.2 Structure of the Unite Inventory for a given SDM is beyond the scope of this document. The A-LINK
Trade Organization is responsible for the management of this information.
7.5.1.5 A-LINK States and Diagnostics
7.5.1.5.1 Attributes related to device state are categorized and handled as Unite State information. For example two
attributes of the DM object listed in Table 2 that are identified with an alternative access instruction of Unite States
are mapped into the A-LINK Unite States as specified in this section. See the A-LINK standard for a description of
the Unite States.
7.5.1.5.2 These two attributes are mapped into the Unite State data structure. Additional diagnostic data may be
included with DP Facility as specified by A-LINK.
7.5.2 A-LINK I/O Data Exchange
7.5.2.1 Input/Output attributes of the Application objects are communicated using the I/O Data Exchange
instruction of A-LINK. This instruction is described in the A-LINK standard. A list of which attributes are
accessible with this instruction is included in the A-LINK Device Profile for a given device type.
7.5.3 A-LINK Device Configuration
7.5.3.1 Configuration attributes of the DM object and Application objects are communicated using the Unite
Inventory Service of A-LINK. This service is described in the A-LINK standard. A list of which Application object
attributes are accessible with this instruction is included in the A-LINK Device Profile for a given device type.
7.5.3.2 Attribute Identifiers
7.5.3.2.1 Every class object specified in the CDM uses attribute identifier tags to identify its attributes. The tags are
formed with alphabetic part of its object identifier tag, a character ‘A’ for impressing attribute and a numerical
identifier of the attribute. The numerical identifier is assigned to the Attribute ID used in the A-LINK NCS for
classes DM, SAC, Assembly, Local Link, AE, S, A and C, as described in following tables: i.e. from Table 2
through Table 8.
7.5.3.2.2 Except Sensor-Binary Input Threshold (SBITH) class, the Attribute ID used in the A-LINK for derived
classes of Sensor and Actuator classes is assigned with the same manner as above.
7.5.3.2.3 For Sensor-Binary Input Threshold (SBITH) class, the Attribute ID used in the A-LINK starts from 128 to
prevent duplication with the numerical identifiers in CDM assigned and reserved to is parent class, SBI.
7.5.3.2.4 The A-LINK attribute ID is used to identify attributes for access via A-LINK message requests, which are
explained in later sections.
7.5.4 A-LINK Attribute Mappings for CDM
7.5.4.1 Device Manager (DM) Object –– The DM object is the device component responsible for managing and
consolidating the device operation as defined in the CDM standard. Attribute values including DM state are also as
same as defined in the CDM standard. The presentation of object instance attributes to the A-LINK network shall be
as indicated in Table 2.
Table 2 DM Object Attribute Identifiers for A-LINK
Attribute ID
CDM A-LINK
Attribute Name Alternative Access
DmA1 1 Device Type Unite Inventory
DmA2 2 Standard Revision Level Unite Inventory