CAN Controllers and Acceptance Filter 209 May 03, 2004
Philips Semiconductors Preliminary User Manual
LPC2119/2129/2292/2294ARM-based Microcontroller
LUT Error Register (LUTerr - 0xE003 C01C)
EXAMPLES OF ACCEPTANCE FILTER TABLES AND ID INDEX VALUES
Suppose that the five Acceptance Filter address registers contain the values shown in the third column below. In this case each
table contains the decimal number of words and entries shown in the next two columns, and the ID Index field of the CANRFS
register can return the decimal values shown in the rightmost column, for CAN messages whose Identifiers match the entries in
that table.
Figure 38 below is a more detailed and graphic example of the address registers, table layout, and ID Index values. It shows:
• a Standard Individual table starting at the start of Acceptance Filter RAM and containing 26 Identifiers, followed by
• a Standard Group table containing 12 ranges of Identifiers, followed by
• an Extended Individual table containing 3 Identifiers, followed by
• an Extended Group table containing 2 ranges of Identifiers.
Table 153: LUT Error Register (LUTerr - 0xE003 C01C)
LUTerr
Name Function Reset Value
0
This read-only bit is set to 1 if the Acceptance Filter encounters an error in the content of the
tables in AF RAM. It is cleared when software reads the LUTerrAd register. This condition
is ORed with the “other CAN” interrupts from the CAN controllers, to produce the request for
a VIC interrupt channel.
0
Table 154: Example of Acceptance Filter Tables and ID Index Values
Table Register Value # words # entries ID Indexes
Standard Individual SFF_sa 0x040 8
10
16
10
0-15
10
Standard Group SFF_GRP_sa 0x060 4
10
4
10
16-19
10
Extended Individual EFF_sa 0x070 36
10
36
10
20-55
10
Extended Group EFF_GRP_sa 0x100 4
10
2
10
56-57
10
ENDofTable 0x110
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