Samsung S5PC100, Руководство пользователя

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S5PC100 USER’S MANUAL (REV1.0) CCAN
8.5-21
6.2.7 BRP Extension Register
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CAN0_BRP, R/W, Address = 0xEC70_0018
•
CAN1_BRP, R/W, Address = 0xEC80_0018
CANn_BRP Bit Description R/W Reset Value
Reserved [15:4] Reserved R 0
BRPE [3:0] Baud Rate Prescaler Extension
0x00-0x0F: By programming BREP the Baud Rate Prescaler is
extended to values up to 1023. The actual interpretation by the
hardware is that one more than the value programmed by
BRPE (MSBs) and BRP(LSBs) is used.
R/W 0
6.2.8 Message Interface Register Sets
There are two sets of Interface Registers which are used to control the CPU access to the Message RAM. The
Interface Registers avoid conflicts between CPU accesses to the Message RAM and CAN message reception
and transmission by buffering the data to be transferred. A complete Message Object or parts of the Message
Object may be transferred between the Message RAM and the IFx Message Buffer registers in one single
transfer.
The function of the two interface register sets is identical (except for test mode Basic). One set of registers is used
for data transfer to the Message RAM while the other set of registers is used for the data transfer from the
Message RAM, allowing both processes to be interrupted by each other. Figure 6 shows an overview of the two
Interface Register sets.
Each set of Interface Registers consists of Message Buffer Registers controlled by their own Command Registers.
The Command Mask Register specifies the direction of the data transfer and which parts of a Message Object will
be transferred. The Command Request Register is used to select a Message Object in the Message RAM as
target or source for the transfer and to start the action specified in the Command Mask Register.
Base Offset IF2 Register Set Base Offset IF2 Register Set
0x20 IF1 Command Request 0x80 IF2 Command Request
0x24 IF1 Command Mask 0x84 IF2 Command Mask
0x28 IF1 Mask1 0x88 IF2 Mask1
0x2C IF1 Mask2 0x8C IF2 Mask2
0x30 IF1 Arbitration 1 0x90 IF2 Arbitration 1
0x34 IF1 Arbitration 2 0x94 IF2 Arbitration 2
0x38 IF1 Message Control 0x98 IF2 Message Control
0x3C IF1 Data A 1 0x9C IF2 Data A 1
0x40 IF1 Data A 2 0xA0 IF2 Data A 2
0x44 IF1 Data B 1 0xA4 IF2 Data B 1
0x48 IF1 Data B 2 0xA8 IF2 Data B 2