GE PanaFlow MV80, Руководство пользователя

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PanaFlow™ MV80 & MV82 User’s Manual 93
Chapter 4. Serial Communications
4.2.6n Examples (cont.)
An attempt to read register(s) that don't exist:
01 04 00 00 00 50 F1 D2
01 Device address
04 Function code 4 = read input register
00 00 Starting address
00 50 Number of registers = 80
F0 36 CRC
This results in an error response as follows:
01 84 02 C2 C1
01 Device address
84 Function code with most significant bit set indicates error response
02 Exception code 2 = invalid data address
C2 C1 CRC
Request the state all three alarms:
01 02 00 00 00 03 38 0B
01 Device address
02 Function code 2 = read discrete inputs
00 00 Starting address
00 03 Number of inputs = 3
38 0B CRC
and the unit responds with:
01 02 01 02 20 49
01 Device address
02 Function code
01 Number of data bytes = 1
02 Alarm #2 on, alarms #1 and #3 off
20 49 CRC