The mask can be used to look at a group of messages:
To set the mask to filter on the J1939 priority field, the mask would be loaded with:
(01, 06, 02, 04, E0, 00, 00, 00, 00, ED)
To set the mask to filter on the J1939 PGN field, the mask would be loaded with:
(01, 06, 02, 04, 07, FF, F8, 00, 00, 0B)
To set mask to filter on both the priority field and the PGN field the mask would be loaded with:
(01, 06, 02, 04, B7, FF, F8, 00, 00, BB)
Set Filter 1 to 4
Function codes 18 and 19, 28 and 29, 38 and 39, 48 and 49 are filter pairs. These filters are set by sending the desired arbitration code to each filter, 1 to 4. The filters work with the mask function. If the mask is set to zero in a position (don’t care) the value of the filter in that position doesn’t matter.
The filter arbitration field is set to match the aberration code of the incoming message. A match of the filter “and” the mask will pass the message to the PC. The X9 sets the filter On; X8 sets the filter Off, where X=1 through 4. Important: the receiver and each filter must have a different arbitration code. If the receiver and a filter are given the same arbitration code the controller may become erratic. It will need to be
Byte | Byte | Function |
Number | Value |
|
1 | 01 | Start of Frame |
2 | 06 | Control bytes |
3 | 02 | ID byte = J1708 message |
4 | YY | Function byte (18 or 19) (28 or 29) (38 or 39) (48 or 49) |
5 | XX | MSB of arbitration field (J1939 priority bits) |
6 | XX |
|
7 | XX |
|
8 | XX | LSB of arbitration field (J1939 source address) |
9 | 00 | Number of data bytes |
10 | CS | Checksum |
To use the HDV100A3, the filter for a particular J1939 PGN the following procedure must be followed.
1. Turn off the “Receive” function by sending (01, 02, 02, 00, 00, 05).
24 | HDV100A3 Command & Response | |
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PH (815) | FAX (815) |