SAF-C164SM Infineon Technologies, SAF-C164SM Datasheet - Page 355

• Manufacturer Part Number: SAF-C164SM
• Description: 16-Bit CMOS Microcontroller
• Manufacturer: Infineon Technologies

19.3
The message object is the primary means of communication between the CPU and the
CAN controller. Each of the 15 message objects uses 15 consecutive bytes (see
Figure
Note: All message objects must be initialized by the CPU before clearing the INIT bit,
Figure 19-5 Message Object Address Map
The general properties of a message object are defined via the Message Control
Register (MCR). There is a dedicated register MCRn for each message object n.
Each element of the Message Control Register consists of two complementary bits. This
special mechanism allows the selective setting or resetting of specific elements (leaving
others unchanged) without requiring read-modify-write cycles. None of these elements
will be affected by reset.
Table 19-1
Table 19-1
Value
0
0 1
1 0
1 1
User’s Manual
0
even those which are not going to be used.
19-5) and starts at an address that is a multiple of 16.
Function on Write
– Reserved –
Reset element
Set element
Leave element unchanged
The Message Object
shows the functions and meanings of these 2-bit fields.
Reserved
Data0
Data2
Data4
Data6
MCR Bitfield Encoding
Message Control ( MCR)
Arbitration (UAR&LAR)
Msg. Config. ( MCFG)
Data1
Data3
Data5
Data7
19-18
Offset
Meaning on Read
– Reserved –
Element is reset
Element is set
– Reserved –
+0
+2
+4
+6
+8
+10
+12
+14
Object Start Address (EFn0
Message Object 1: EF10
Message Object 2: EF20
...
Message Object 14: EFE0
Message Object 15: EFF0
On-Chip CAN Interface
C164CM/C164SM
MCA04394
Derivatives
V1.0, 2002-02
H
H
H
H
H
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