MC68HC908GZ8 FREESCALE [Freescale Semiconductor, Inc], MC68HC908GZ8 Datasheet - Page 137

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

12.12 Programmer’s Model of Message Storage
This section details the organization of the receive and transmit message buffers and the associated
control registers. For reasons of programmer interface simplification, the receive and transmit message
buffers have the same outline. Each message buffer allocates 16 bytes in the memory map containing a
13-byte data structure. An additional transmit buffer priority register (TBPR) is defined for the transmit
buffers.
12.12.1 Message Buffer Outline
Figure 12-12
identifiers. The mapping of standard identifiers into the IDR registers is shown in
the 13-byte data structure are undefined out of reset.
Freescale Semiconductor
shows the common 13-byte data structure of receive and transmit buffers for extended
The foreground receive buffer can be read anytime but cannot be written.
The transmit buffers can be read or written anytime.
Addr
$05bA
$05bB
$05bC
$05bD
$05bE
$05b0
$05b1
$05b2
$05b3
$05b4
$05b5
$05b6
$05b7
$05b8
$05b9
$05bF
1. Where b equals the following:
2. Not applicable for receive buffers
b=4 for receive buffer
b=5 for transmit buffer 0
b=6 for transmit buffer 1
b=7 for transmit buffer 2
MC68HC908GZ16 • MC68HC908GZ8 Data Sheet, Rev. 4
Figure 12-11. Message Buffer Organization
(1)
TRANSMIT BUFFER PRIORITY REGISTER
DATA SEGMENT REGISTER 0
DATA SEGMENT REGISTER 1
DATA SEGMENT REGISTER 2
DATA SEGMENT REGISTER 3
DATA SEGMENT REGISTER 4
DATA SEGMENT REGISTER 5
DATA SEGMENT REGISTER 6
DATA SEGMENT REGISTER 7
DATA LENGTH REGISTER
IDENTIFIER REGISTER 0
IDENTIFIER REGISTER 1
IDENTIFIER REGISTER 2
IDENTIFIER REGISTER 3
NOTE
Register Name
UNUSED
UNUSED
Programmer’s Model of Message Storage
(2)
Figure
12-13. All bits of
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