HD6432646 Hitachi, HD6432646 Datasheet - Page 12

• Manufacturer Part Number: HD6432646
• Description: (HD64F264x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

Section
15.3.2 Initialization
after Hardware
Reset
Bit Rate and Bit
Timing Settings
565 to
567
Page
Description
Table 15-4
Notes: The time quanta value for TSEG1 and TSEG2 is the TSEG value + 1.
(BCR [11:8])
Example: With a 1 Mb/s baud rate and a 20 MHz input clock:
HCAN bit rate calculation:
BCR Setting Constraints
These constraints allow the setting range shown in table 15-4 for TSEG1 and TSEG2 in BCR.
1-bit time
Legend
SYNC_SEG: Segment for establishing synchronization of nodes on the CAN bus. (Normal
PRSEG:
PHSEG1:
PHSEG2:
Note:
TSEG1
* Only a value other than BRP[13:8] = B'000000 can be set.
Bit rate =
Note: f
TSEG1 > TSEG2
1 Mb/s =
The time quanta values of TSEG1 and TSEG2 become the value of TSEG + 1.
Set Values
f
BRP = 0 (B'000000)
TSEG1 = 4 (B'0100)
TSEG2 = 3 (B'011)
SYNC_SEG
CLK
Setting Range for TSEG1 and TSEG2 in BCR
= 20 MHz
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
1
The BCR values are used for BRP, TSEG1, and TSEG2.
bit edge transitions occur in this segment.)
Segment for compensating for physical delay between networks.
Buffer segment for correcting phase drift (positive). (This segment is extended
when synchronization (resynchronization) is established.)
Buffer segment for correcting phase drift (negative). (This segment is
shortened when synchronization (resynchronization) is established.)
CLK
2
2
= ø (system clock)
Figure 15-6 Detailed Description of Timing within 1 Bit
(0 + 1)
(BRP + 1)
Yes*
Yes*
Yes*
Yes*
Yes*
Yes*
Yes*
Yes*
Yes*
Yes*
Yes*
Yes*
001
No
20 MHz
SJW
1-bit time (8–25 time quanta)
(3 + 4 + 3)
PRSEG
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
010
TSEG1 (time segment 1)
(3 + TSEG1 + TSEG2)
(SJW = 0 to 3)
f
CLK
Actual Values
—
System clock
5TQ
4TQ
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
TSEG2 (BCR [14:12])
011
No
2–16
PHSEG1
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
100
No
No
2
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
101
No
No
No
TSEG2 (time segment 2)
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
110
No
No
No
No
PHSEG2
2–8
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
111
No
No
No
No
No
Quantum