FlexCAN
Freescale Semiconductor
30-16
MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
30.3.8
Interrupt Flag Register (IFLAG)
IFLAG contains one interrupt flag bit per buffer. Each successful transmission/reception sets the
corresponding IFLAG bit and, if the corresponding IMASK bit is set, generates an interrupt.
The interrupt flag is cleared by writing a 1, while writing 0 has no effect.
30.3.9
Message Buffer Structure
The message buffer memory map starts at an offset of 0x80 from the FlexCAN’s base address
(0x1C_0000). The 256-byte message buffer space is fully used by the16 message buffer structures.
Each message buffer consists of a control and status field that configures the message buffer, an identifier
field for frame identification, and up to 8 bytes of data.
Table 30-9. IMASK Field Descriptions
Field
Description
31–16
Reserved, must be cleared.
15–0
BUFnM
Buffer interrupt mask. Enables the respective FlexCAN message buffer (MB0 to MB15) interrupt. These bits allow
the CPU to designate which buffers generate interrupts after successful transmission/reception.
0 The interrupt for the corresponding buffer is disabled.
1 The interrupt for the corresponding buffer is enabled.
Note: Setting or clearing an IMASK bit can assert or negate an interrupt request, if the corresponding IFLAG bit it
is set.
IPSBAR
Offset:
0x1C_0030 (IFLAG)
Access: User read/write
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
R 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
BUFnI
W
w1c
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Figure 30-11. FlexCAN Interrupt Flags Register (IFLAG)
Table 30-10. IFLAG Field Descriptions
Field
Description
31–16
Reserved, must be cleared.
15–0
BUFnI
Buffer interrupt flag. Indicates a successful transmission/reception for the corresponding message buffer. If the
corresponding IMASK bit is set, an interrupt request is generated. The user must write a 1 to clear an interrupt flag;
writing 0 has no effect.
0 No such occurrence.
1 The corresponding buffer has successfully completed transmission or reception.
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International
Trade
Commission,
BGA-packaged
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sale
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prior
to
September
2010:MCF52234CVM60,
MCF52235CVM60
