Datasheet

Chapter 16 Freescale’s Scalable Controller Area Network (S12MSCANV3)
MC9S12XE-Family Reference Manual Rev. 1.25
Freescale Semiconductor 617
The bit time is determined by the oscillator frequency, the baud rate prescaler, and the number of time
quanta (Tq) clock cycles per bit (as shown in Table 16-9 and Table 16-10).
Eqn. 16-1
16.3.2.5 MSCAN Receiver Flag Register (CANRFLG)
A flag can be cleared only by software (writing a 1 to the corresponding bit position) when the condition
which caused the setting is no longer valid. Every flag has an associated interrupt enable bit in the
CANRIER register.
Table 16-9. Time Segment 2 Values
TSEG22 TSEG21 TSEG20 Time Segment 2
0 0 0 1 Tq clock cycle
(1)
1. This setting is not valid. Please refer to Table 16-37 for valid settings.
0 0 1 2 Tq clock cycles
::: :
1 1 0 7 Tq clock cycles
1 1 1 8 Tq clock cycles
Table 16-10. Time Segment 1 Values
TSEG13 TSEG12 TSEG11 TSEG10 Time segment 1
0 0 0 0 1 Tq clock cycle
(1)
1. This setting is not valid. Please refer to Table 16-37 for valid settings.
0 0 0 1 2 Tq clock cycles
1
0 0 1 0 3 Tq clock cycles
1
0 0 1 1 4 Tq clock cycles
:::: :
1 1 1 0 15 Tq clock cycles
1 1 1 1 16 Tq clock cycles
Module Base + 0x0004 Access: User read/write
(1)
76543210
R
WUPIF CSCIF
RSTAT1 RSTAT0 TSTAT1 TSTAT0
OVRIF RXF
W
Reset: 00000000
= Unimplemented
Figure 16-8. MSCAN Receiver Flag Register (CANRFLG)
Bit Time
Prescaler value()
f
CANCLK
------------------------------------------------------
1 TimeSegment1 TimeSegment2++()•=