Nodeutil is a low level free but unsupported utility that allows the user to look at the characteristics of individual devices on a network.
Amongst other things, users can look at the error statistics stored in the neuron chip. This article look at those related to messages sent to and from a device.
When you are in the Device Menu, select the <S> option to Report Device Status and Statistics for that particular device.
Clear the Statistics as indicated in the screen output to start from a known point.
When you clear the device statistics you will have a count of :
Packets received by device = 4
Packets addressed to device = 4
Messages sent to MAC layer = 4
Say the device receives 10 other messages addressed to it because the messages were Domain wide broadcast i.e. addressed to every device on the network. Using the <S> option again will yield these statistics
Packets received by device = 14
Packets addressed to device = 14
Messages sent to MAC layer = 4
As the receiving device did not send any message out to the network, no messages were sent to the MAC layer. If the service type was Ackd (which you cannot set with Domain Broadcast) you would have seen additional messages sent to the MAC layer.
Note that ALL messages on the segment of wire that devices are attached to are received by the MAC layer as indicated by **Packets received by device**. These messages are then passed up the protocol stack as long the messages pass the CRC check. If they do not pass CRC check the message is deemed as corrupted, is ignored at the MAC level and not passed up the network CPU where the destination address of the packet is looked at and neither is the packet passed to the application for processing. A Packet error is then logged.
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