PROFIBUS DP (COM465DP only)
27
COM465IP-COM465DP_D00216_02_M_XXEN/03.2017
5.1.5 Data access using PROFIBUS DP
PROFIBUS DP offers three methods for reading or writing data:
– Type 1: Querying measured data from devices on the bus
– Type 2: Querying registers in devices on the bus
– Type 3: Writing to registers on devices on the bus
5.1.5.1 Type 1: Querying measured data from devices on the bus
Request to the gateway:
Response from the gateway:
Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 Byte 8 Byte 9
Byte 10
ID
Msg
type
System Device Channel 0x00 0x00 0x00 0x00 0x00 0x00
Byte 0: Sequential ID no.: Must be set by the person programming the PROFIBUS DP master. The
ID no. must be incremented for the next request as soon as a response has been received
to the previous request.
Byte 1: Message type: For this request always 0x01
Byte 2: Subsystem address: Depending on how the device is operated, either the BCOM or the
external BMS bus address (default for usage on the internal BMS bus: 2)
Byte 3: Device address: The internal BMS or BCOM address. Depends on which interface is used to
integrate the device.
Byte 4: Channel: The channel that is to be queried.
Byte 5-10: Always 0x00
Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 Byte 8 Byte 9
ID
Data
value
high
high
Data
value
high
low
Data
value
low
high
Data
value
low
low
Alarm
& test
Range
& unit
Descrip-
tion high
Descrip-
tion low
0xFF
Byte 0: Sequential ID no.
Byte 1-4: Measured values: The data are output as a floating point value.
Byte 5: Alarm type and test type
For details see "A&T = Alarm type and test type (internal/external)" on page 45.
Alarm type & test
Test ext. 7
Test int. 6
State 5
Res. 4
Res. 3
Alarm
2
1
0
To Next Page
Loading...