Chapter 16 Freescale’s Scalable Controller Area Network (S12MSCANV3)
MC9S12XE-Family Reference Manual , Rev. 1.19
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Freescale Semiconductor
— a) the 14 most significant bits of the extended identifier plus the SRR and IDE bits of CAN 2.0B
messages or
— b) the 11 bits of the standard identifier, the RTR and IDE bits of CAN 2.0A/B messages.
shows how the first 32-bit filter bank (CANIDAR0–CANIDA3,
CANIDMR0–3CANIDMR) produces filter 0 and 1 hits. Similarly, the second filter bank
(CANIDAR4–CANIDAR7, CANIDMR4–CANIDMR7) produces filter 2 and 3 hits.
•
Eight identifier acceptance filters, each to be applied to the first 8 bits of the identifier. This mode
implements eight independent filters for the first 8 bits of a CAN 2.0A/B compliant standard
identifier or a CAN 2.0B compliant extended identifier.
shows how the first 32-bit
filter bank (CANIDAR0–CANIDAR3, CANIDMR0–CANIDMR3) produces filter 0 to 3 hits.
Similarly, the second filter bank (CANIDAR4–CANIDAR7, CANIDMR4–CANIDMR7)
produces filter 4 to 7 hits.
•
Closed filter. No CAN message is copied into the foreground buffer RxFG, and the RXF flag is
never set.
Figure 16-40. 32-bit Maskable Identifier Acceptance Filter
ID28
ID21
IDR0
ID10
ID3
IDR0
ID20
ID15
IDR1
ID2
IDE
IDR1
ID14
ID7
IDR2
ID10
ID3
IDR2
ID6
RTR
IDR3
ID10
ID3
IDR3
AC7
AC0
CANIDAR0
AM7
AM0
CANIDMR0
AC7
AC0
CANIDAR1
AM7
AM0
CANIDMR1
AC7
AC0
CANIDAR2
AM7
AM0
CANIDMR2
AC7
AC0
CANIDAR3
AM7
AM0
CANIDMR3
ID Accepted (Filter 0 Hit)
CAN 2.0B
Extended Identifier
CAN 2.0A/B
Standard Identifier
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:
S12XE
products
in
208
MAPBGA
packages