APARIAN A-HRT-4I, Руководство пользователя

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Operation
Document No. D113-015 Page 39 of 77
Revision 1.9
The required Request and Response HART Command structures are defined as follows:
HART Command Request
Byte
Offset
Data
Type Description
0 INT Request Length
2 SINT Start Character (0x82 for Long Address)
3 SINT Long Address 0 (0x80 + Manufacturer ID)
4 SINT Long Address 1 (Device Type Code)
5 SINT Long Address 2 (Device ID Byte 0)
6 SINT Long Address 3 (Device ID Byte 1)
7 SINT Long Address 4 (Device ID Byte 2)
8 SINT Command Code
9 SINT Command Data Length (in bytes)
10 SINT[] Command Data (If required)
Table 4.4 – Relay HART Message Request Structure
HART Command Response
Byte Offset Data Type Description
0 INT Status (See table below)
2 INT Packet Length
4 SINT Start Character
5 SINT Long Address 0
6 SINT Long Address 1
7 SINT Long Address 2
8 SINT Long Address 3
9 SINT Long Address 4
10 SINT Command Code (Echoed)
11 SINT Reply Data Length
12 INT Status (Same as at byte 0 above).
14 SINT[] Command Reply Data
Table 4.5 – Relay HART Message Response Structure
4.1.3.1. HART COMMAND STATUS ENCODING
The Status code returned in the HART relay command can be decoded as follows:
To determine which table to use, first examine the value of the bit 7 in the first byte.
If Byte 0 Bit 7 = 0 then:
First Byte : Command Errors
Value Description
0 No error