MC68HC908GZ8 FREESCALE [Freescale Semiconductor, Inc], MC68HC908GZ8 Datasheet - Page 139

• Manufacturer Part Number: MC68HC908GZ8
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

12.12.2 Identifier Registers
The identifiers consist of either 11 bits (ID10–ID0) for the standard, or 29 bits (ID28–ID0) for the extended
format. ID10/28 is the most significant bit and is transmitted first on the bus during the arbitration
procedure. The priority of an identifier is defined to be highest for the smallest binary number.
SRR — Substitute Remote Request
IDE — ID Extended
RTR — Remote Transmission Request
Freescale Semiconductor
Addr.
$05b0
$05b1
$05b2
$05b3
This fixed recessive bit is used only in extended format. It must be set to 1 by the user for transmission
buffers and will be stored as received on the CAN bus for receive buffers.
This flag indicates whether the extended or standard identifier format is applied in this buffer. In case
of a receive buffer, the flag is set as being received and indicates to the CPU how to process the buffer
identifier registers. In case of a transmit buffer, the flag indicates to the MSCAN08 what type of
identifier to send.
This flag reflects the status of the remote transmission request bit in the CAN frame. In case of a
receive buffer, it indicates the status of the received frame and supports the transmission of an
answering frame in software. In case of a transmit buffer, this flag defines the setting of the RTR bit to
be sent.
1 = Extended format, 29 bits
0 = Standard format, 11 bits
1 = Remote frame
0 = Data frame
Register
IDR0
IDR1
IDR2
IDR3
Read:
Read:
Read:
Read:
Write:
Write:
Write:
Write:
MC68HC908GZ16 • MC68HC908GZ8 Data Sheet, Rev. 4
Figure 12-13. Standard Identifier Mapping
Bit 7
ID10
ID2
= Unimplemented
ID9
ID1
6
ID8
ID0
5
RTR
ID7
4
Programmer’s Model of Message Storage
IDE (=0)
ID6
3
ID5
2
ID4
1
Bit 0
ID3
139