分类： IT职场
2010-03-05 00:03:38
Variable Management
1. Read request
MMSPdu Received ::=
A0 1E 02 01 0A A4 19 A1 17 A0 15 30 13 A0 11 80 0F 66 65 65 64 65 72 31 5F 33 5F 70 68 61 73 65
[0] A0 1E -- ConfirmedRequestPDU
{
02 01 0A -- invokeID
[4] A4 19 -- ConfirmedServiceRequest, A4 = Read
{
[1] A1 17 -- variableAccessSpecification
{
[0] 30 13 -- listOfVariable
(30 = 00 1 10000, Universal Constructed)
{
[0] A0 11 -- variableSpecification
{
[0] 80 0F 66 65 65 64 65 72 31 5f 33 5f 70 68 61 73 65 -- name
}
}
}
}
}
where,
invokeID::=0A
Identifier (name of variable to read)::="feeder1_3_phase"
2. Read response
Assume
typedef struct var_def
{
int a;
int b;
} VAR_DEF;
VAR_DEF feeder1_3_phase;
MMS Data Production
Data ::= CHOICE
{
[1] IMPLICIT SEQUENCE OF,-- arrayed data
[2] IMPLICIT SEQUENCE OF,-- structured data
[3] IMPLICIT BOOLEAN,
[4] IMPLICIT BIT STRING,
[5] IMPLICIT INTEGER,-- signed int
[6] IMPLICIT INTEGER,-- unsigned int
[7] IMPLICIT Floating Point,
[9] IMPLICIT OCTET STRING,
[10] IMPLICIT VisibleString,
[11] IMPLICIT GeneralizedTime,
[12] IMPLICIT TimeofDay,
[13] IMPLICIT INTEGER,-- BCD
[14] IMPLICIT BIT STRING,-- boolean array
[15] IMPLICIT OBJECT IDENTIFIER
}
The encoded structure of the encoded data can be determined via VAR_DEF
VAR_DEF::= TAG
-------------------------------------------
struct { A2
inta; 85
intb; 85
}
MMSPdu Received ::=
A1 0F 02 01 0A A4 0A A1 08 A2 06 85 01 00 85 0100
[1] A1 0F -- ConfirmedResponsePDU
{
02 01 0A -- invokeID
[4] A4 0A -- ConfirmedServiceResponse, A4 = Read
{
[1] OF A1 08 -- listOfAccessResult
{
A2 06 -- success, Data of struct
{
85 01 00 -- int a;
85 01 00 -- int b;
}
}
}
}
where,
invokeID::=0A
value of a::=00, value of b::=00
