Volttron，BACnet 设备不支持分段

Question

你好，

希望你一切顺利。

我正在从 AHU 读取数据，但在获取对象列表时出现错误：分段不支持。在发送 WhoIsIAm (bacnet_scan.py) 时，我收到以下回复：

Device Address        = <RemoteStation 4100:9>
Device Id             = 409
maxAPDULengthAccepted = 206
segmentationSupported = noSegmentation
vendorID              = 17

我的客户端应用程序 (grab_bacnet_config.py) 的配置是：

[BACpypes]
objectName: Betelgeuse
address: myIP/24
objectIdentifier: 599
maxApduLengthAccepted: 206 
segmentationSupported: segmentedBoth
vendorIdentifier: 15

我将 maxApduLengthAccepted 更改为远程设备的。还试图让它足够大以容纳其他设备。阅读其他问题尝试使用 bacpypes github 存储库提供的 ReadProperty 进行调试。

python read.py --debug bacpypes.appservice.ClientSSM
DEBUG:bacpypes.consolelogging.ConfigArgumentParser:__init__
DEBUG:bacpypes.consolelogging.ArgumentParser:__init__
DEBUG:bacpypes.consolelogging.ConfigArgumentParser:update_os_env
DEBUG:bacpypes.consolelogging.ArgumentParser:update_os_env
DEBUG:bacpypes.consolelogging.ArgumentParser:    - settings: {'debug_file': '', 'debug': set([]), 'max_bytes': 1048576, 'color': False, 'backup_count': 5, 'route_aware': False}
DEBUG:bacpypes.consolelogging.ArgumentParser:    - os environment
DEBUG:bacpypes.consolelogging.ArgumentParser:parse_args
DEBUG:bacpypes.consolelogging.ConfigArgumentParser:expand_args Namespace(buggers=False, color=None, debug=['bacpypes.appservice.ClientSSM'], ini='BACpypes.ini', route_aware=None)
DEBUG:bacpypes.consolelogging:    - config: <ConfigParser.ConfigParser instance at 0x7fa5066dc0>
DEBUG:bacpypes.consolelogging:    - ini_obj: {'objectidentifier': '599', 'segmentationsupported': 'segmentedReceive', 'objectname': 'Betelgeuse', 'address': 'myIP/24', 'vendoridentifier': '15', 'maxapdulengthaccepted': '206'}
DEBUG:bacpypes.consolelogging.ArgumentParser:expand_args Namespace(buggers=False, color=None, debug=['bacpypes.appservice.ClientSSM'], ini={'objectidentifier': '599', 'segmentationsupported': 'segmentedReceive', 'objectname': 'Betelgeuse', 'address': 'myIP/24', 'vendoridentifier': '15', 'maxapdulengthaccepted': '206'}, route_aware=None)
DEBUG:bacpypes.consolelogging.ArgumentParser:    - debug: ['bacpypes.appservice.ClientSSM']
DEBUG:bacpypes.consolelogging.ArgumentParser:    - color not specified
DEBUG:bacpypes.consolelogging.ArgumentParser:    - route_aware not specified
DEBUG:bacpypes.consolelogging.ArgumentParser:    - args expanded
DEBUG:bacpypes.consolelogging.ArgumentParser:interpret_debugging Namespace(buggers=False, color=None, debug=['bacpypes.appservice.ClientSSM'], ini={'objectidentifier': '599', 'segmentationsupported': 'segmentedReceive', 'objectname': 'Betelgeuse', 'address': 'myIP/24', 'vendoridentifier': '15', 'maxapdulengthaccepted': '206'}, route_aware=None)
DEBUG:bacpypes.consolelogging.ArgumentParser:    - settings: {'debug_file': '', 'debug': set(['bacpypes.appservice.ClientSSM']), 'max_bytes': 1048576, 'ini': 'BACpypes.ini', 'color': False, 'backup_count': 5, 'route_aware': False}
DEBUG:bacpypes.consolelogging.ArgumentParser:    - interpreted debugging
> read 4100:9 device:409 objectList 
DEBUG:bacpypes.appservice.ClientSSM:__init__ <bacpypes.appservice.StateMachineAccessPoint object at 0x7fa50736d0> <Address 4100:9>
DEBUG:bacpypes.appservice.ClientSSM:indication <bacpypes.apdu.ConfirmedRequestPDU(12,1) instance at 0x7fa5073ed0>
    <bacpypes.apdu.ConfirmedRequestPDU(12,1) instance at 0x7fa5073ed0>
        pduDestination = <Address 4100:9>
        pduExpectingReply = 1
        pduNetworkPriority = 0
        apduType = 0
        apduService = 12
        apduInvokeID = 1
        pduData = x'0c.02.00.10.71.19.4c'
DEBUG:bacpypes.appservice.ClientSSM:    - segment size: 206
DEBUG:bacpypes.appservice.ClientSSM:    - invoke ID: 1
DEBUG:bacpypes.appservice.ClientSSM:    - segment count: 1
DEBUG:bacpypes.appservice.ClientSSM:set_state 2 (AWAIT_CONFIRMATION) timer=3000
DEBUG:bacpypes.appservice.ClientSSM:request <bacpypes.apdu.ConfirmedRequestPDU(12,1) instance at 0x7fa50733d0>
    <bacpypes.apdu.ConfirmedRequestPDU(12,1) instance at 0x7fa50733d0>
        pduDestination = <Address 4100:9>
        pduExpectingReply = 1
        pduNetworkPriority = 0
        apduType = 0
        apduSeg = False
        apduMor = False
        apduSA = True
        apduMaxSegs = 4
        apduMaxResp = 2
        apduService = 12
        apduInvokeID = 1
        pduData = x'0c.02.00.10.71.19.4c'
DEBUG:bacpypes.appservice.ClientSSM:confirmation <bacpypes.apdu.AbortPDU(None,1) instance at 0x7fa51ab650>
    <bacpypes.apdu.AbortPDU(None,1) instance at 0x7fa51ab650>
        pduSource = <RemoteStation 4100:9>
        pduDestination = <Address myIP>
        pduExpectingReply = False
        pduNetworkPriority = 0
        apduType = 7
        apduSrv = True
        apduInvokeID = 1
        apduAbortRejectReason = 4
        pduData = x''
DEBUG:bacpypes.appservice.ClientSSM:await_confirmation <bacpypes.apdu.AbortPDU(None,1) instance at 0x7fa51ab650>
    <bacpypes.apdu.AbortPDU(None,1) instance at 0x7fa51ab650>
        pduSource = <RemoteStation 4100:9>
        pduDestination = <Address myIP>
        pduExpectingReply = False
        pduNetworkPriority = 0
        apduType = 7
        apduSrv = True
        apduInvokeID = 1
        apduAbortRejectReason = 4
        pduData = x''
DEBUG:bacpypes.appservice.ClientSSM:    - server aborted
DEBUG:bacpypes.appservice.ClientSSM:set_state 7 (ABORTED) timer=0
DEBUG:bacpypes.appservice.ClientSSM:    - remove from active transactions
DEBUG:bacpypes.appservice.ClientSSM:response <bacpypes.apdu.AbortPDU(None,1) instance at 0x7fa51ab650>
    <bacpypes.apdu.AbortPDU(None,1) instance at 0x7fa51ab650>
        pduSource = <RemoteStation 4100:9>
        pduDestination = <Address myIP>
        pduExpectingReply = False
        pduNetworkPriority = 0
        apduType = 7
        apduSrv = True
        apduInvokeID = 1
        apduAbortRejectReason = 4
        pduData = x''
segmentationNotSupported

也尝试使 APDU 长度足够大并等于远程设备的长度，但仍然无法读取 objectList。我能够读取单个属性及其值，但不能读取整个对象列表。我可以读吗？我需要将它们放在@volttron 中用于 grab_bacnet_config.py 脚本。有没有办法调整 apdu 长度或分段内容？

此致，穆罕默德·阿纳斯·拉扎

Answer 1

仅仅因为您的客户端可以（假设）支持“双向”方向的分段 - 传输和接收，server/device/AHU 不支持。

因此，为了读取完整的对象列表，您必须回退到遍历对象列表数组 - 一次一个元素。

Element/array-index数组的0（-第一个元素），包含数据元素个数的count；对于您想要阅读的每个元素 - 包括第一个 one/element，您必须指定您想要阅读的 target/desired element/index。

Volttron，BACnet 设备不支持分段

Volttron, noSegmentationSupported for BACnet devices

python

volttron

bacnet