Datasheet

MSCAN Controller (MSCAN08)
MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
296 Freescale Semiconductor
23.13.9 MSCAN08 Identifier Acceptance Control Register
IDAM1–IDAM0— Identifier Acceptance Mode
The CPU sets these flags to define the identifier acceptance filter organization (see 23.5 Identifier
Acceptance Filter). Table 23-9 summarizes the different settings. In “filter closed” mode no messages
will be accepted so that the foreground buffer will never be reloaded.
IDHIT1–IDHIT0— Identifier Acceptance Hit Indicator
The MSCAN08 sets these flags to indicate an identifier acceptance hit (see 23.5 Identifier Acceptance
Filter). Table 23-9 summarizes the different settings.
The IDHIT indicators are always related to the message in the foreground buffer. When a message gets
copied from the background to the foreground buffer, the indicators are updated as well.
NOTE
The CIDAC register can be written only if the SFTRES bit in the CMCR0 is
set.
Address: $0508
Bit 7654321Bit 0
Read: 0 0
IDAM1 IDAM0
0 0 IDHIT1 IDHIT0
Write:
Reset:00000000
= Unimplemented
Figure 23-23. Identifier Acceptance Control Register (CIDAC)
Table 23-9. Identifier Acceptance Mode Settings
IDAM1 IDAM0 Identifier Acceptance Mode
0 0 Single 32-Bit Acceptance Filter
0 1 Two 16-Bit Acceptance Filter
1 0 Four 8-Bit Acceptance Filters
1 1 Filter Closed
Table 23-10. Identifier Acceptance Hit Indication
IDHIT1 IDHIT0 Identifier Acceptance Hit
0 0 Filter 0 Hit
0 1 Filter 1 Hit
1 0 Filter 2 Hit
1 1 Filter 3 Hit