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Chapter 13 FlexRay Communication Controller (FLEXRAY)
MC9S12XF - Family Reference Manual, Rev.1.19
Freescale Semiconductor
471
13.5.2.4
Module Conguration Register (MCR)
This register denes the global conguration of the FlexRay block.
Module Base + 0x0002
15
14
13
12
11
10
9876543210
R
MEN
0
SCM
CHB
CHA
SFFE
0
R*
000
CLKS
EL
BITRATE
0
W
Reset
0000000000000000
Figure 13-3. Module Conguration Register (MCR)
Write: MEN, SCM, CHB, CHA, CLKSEL, BITRATE: Disabled Mode
SFFE: Disabled Mode or POC:cong
Table 13-8. MCR Field Descriptions
Field
Description
15
MEN
Module Enable — This bit indicates whether or not the FlexRay block is in the Disabled Mode. The application
requests the FlexRay block to leave the Disabled Mode by writing 1 to this bit. Before leaving the Disabled Mode,
the application must congure the SCM, CHB, CHA, TMODE, CLKSEL, BITRATE values. For details see
0 Write: ignored, FlexRay block disable not possible
Read: FlexRay block disabled
1 Write: enable FlexRay block
Read: FlexRay block enabled
Note: If the FlexRay block is enabled it can not be disabled.
13
SCM
Single Channel Device Mode — This control bit denes the channel device mode of the FlexRay block as
0 FlexRay block works in dual channel device mode
1 FlexRay block works in single channel device mode
12–11
CHB
CHA
Channel Enable — protocol related parameter: pChannels
The semantic of these control bits depends on the channel device mode controlled by the SCM bit and is given
10
SFFE
Synchronization Frame Filter Enable — This bit controls the ltering for received synchronization frames. For
0 Synchronization frame ltering disabled
1 Synchronization frame ltering enabled
8
R*
Reserved — This bit is reserved. It is read as 0. Application must not write 1 to this bit.
4
CLKSEL
Protocol Engine Clock Source Select — This bit is used to select the clock source for the protocol engine.
0 PE clock source is generated by on-chip crystal oscillator.
1 PE clock source is generated by on-chip PLL.
3–1
BITRATE
FlexRay Bus Bit Rate — This bit eld denes the bit rate of the exray channels according to
Table 13-10. Table 13-9. FlexRay Channel Selection (Sheet 1 of 2)
SCM
CHB
CHA
Description
Dual Channel Device Modes