9853 Message Acceptance Filter

[RigilKumar]

Goodmorning All

                  I am using Compact RIO NI 9012 and NI CAN 9853 hardwares for my application. I want to enable Message Acceptance Input filter for CAN module.

For that I selected the SJA format filter  and then  manually calculated the SJA1000 Mask and code according to the arbitration ID required, and written to the property node of CAN. But no messages are filtered out. Is there is any other parameter i should taken care to accept specific arbitration ID's?.

can you explain step by step procedure to implement message acceptance filter.?

Thank & Regards

Rigil Kumar

[MXI Master]

Rigil,

To do this you need to set three properties: Interface Series 2 Comparator, Interface Series 2 Filter Mode, and Interface Series 2 Mask.

The Interface Series 2 Comparator specifies a comparator value that is checked against the ID, RTR, and data bits. The Interface Series 2 Mask determines the applicable bits for comparison.

The default value of this property is zero.

The mapping of bits in this property to the ID, RTR, and data bits of incoming frames is determined by the value of the Interface Series 2 Filter Mode property. The Series 2 filter mode determines the format of this property as well as the Series 2 mask.

From what you have stated, I have a feeling you are probably setting the Comparator but not the Mask.  Without the mask set all messages will get passed. This information is all avilable in the NI-CAN help file.

Message Edited by MXI Master on 03-07-2008 02:41 PM