msm9225 Oki Semiconductor, msm9225 Datasheet - Page 17

• Manufacturer Part Number: msm9225
• Description: Can Controller Area Network Controller
• Manufacturer: Oki Semiconductor

¡ Semiconductor
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(2)
(1) Baud rate prescaler: BRP5 to BRP0
This is a 6-bit prescaler to set the BTL cycle time and SJW of the basic clock for
communication operation.
The relationship between the bit content and BTL is as follows:
At reset, BRP5 to BRP0 are set to "000000".
BTL cycle time = 2 ¥ (2
System clock is 1/2 division of oscillation frequency.
f
SJW: SJWA, SJWB
The relationship between bit content and SJW is as follows:
At reset, SJWA and SJWB are set to “00”.
The BTL cycle time is given by the following operation.
This is a 2-bit register to set SJW.
BRP5
OSC
0
0
1
1
SJWB
·
·
0
0
1
1
is the oscillation frequency.
BRP4
0
0
1
1
·
·
SJWA
0
1
0
1
BRP3
+ 1)/f
0
0
1
1
·
·
5
OSC
BRP2
¥ BRP5 + 2
1 ¥ BTL cycle
2 ¥ BTL cycle
3 ¥ BTL cycle
4 ¥ BTL cycle
SJW1, SJW2
0
0
1
1
·
·
BRP1
0
0
1
1
·
·
4
¥ BRP4 + 2
BRP0
0
1
0
1
·
·
3
¥ BRP3 + 2
63X system clock cycle
64X system clock cycle
1X system clock cycle
2X system clock cycle
BTL cycle time
2
¥ BRP2 + 2
·
·
1
¥ BRP1 + BRP0
MSM9225
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