s908az32ag2cfue Freescale Semiconductor, Inc, s908az32ag2cfue Datasheet - Page 281

• Manufacturer Part Number: s908az32ag2cfue
• Description: M68hc08 Microcontrollers 8-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

24.12.4 Data Segment Registers (DSRn)
The eight data segment registers contain the data to be transmitted or received. The number of bytes to
be transmitted or being received is determined by the data length code in the corresponding DLR.
24.12.5 Transmit Buffer Priority Registers
PRIO7–PRIO0 — Local Priority
24.13 Programmer’s Model of Control Registers
The programmer’s model has been laid out for maximum simplicity and efficiency.
overview on the control register block of the MSCAN08.
Freescale Semiconductor
This field defines the local priority of the associated message buffer. The local priority is used for the
internal prioritisation process of the MSCAN08 and is defined to be highest for the smallest binary
number. The MSCAN08 implements the following internal prioritisation mechanism:
•
•
•
All transmission buffers with a cleared TXE flag participate in the prioritisation right before the SOF
is sent.
The transmission buffer with the lowest local priority field wins the prioritisation.
In case more than one buffer has the same lowest priority, the message buffer with the lower index
number wins.
Address:
Reset:
Read:
Write:
Figure 24-13. Transmit Buffer Priority Register (TBPR)
$05bD
PRIO7
Bit 7
u
DLC3
0
0
0
0
0
0
0
0
1
PRIO6
6
u
MC68HC908AZ32A Data Sheet, Rev. 2
Table 24-5. Data Length Codes
Data Length Code
DLC2
0
0
0
0
1
1
1
1
0
PRIO5
5
u
DLC1
0
0
1
1
0
0
1
1
0
PRIO4
4
u
DLC0
PRIO3
0
1
0
1
0
1
0
1
0
3
u
Programmer’s Model of Control Registers
PRIO2
Data Byte
2
u
Count
0
1
2
3
4
5
6
7
8
PRIO1
1
u
Figure 24-14
PRIO0
Bit 0
u
gives an
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