mcf51ac256a Freescale Semiconductor, Inc, mcf51ac256a Datasheet - Page 22

• Manufacturer Part Number: mcf51ac256a
• Description: Mcf51ac Flexis
• Manufacturer: Freescale Semiconductor, Inc

Device Overview
1.3
The MCF51AC256 series devices contain a version of the V1 ColdFire core that is optimized for area of
low power. This CPU implements ColdFire instruction set architecture revision C (ISA_C) plus adds
support for real-time program trace capability:
For more details on the V1 ColdFire core, see
1.3.1
Figure 1-2
registers:
1.3.2
System programmers use the supervisor programming model to implement operating system functions.
All accesses that affect the control features of ColdFire processors must be made in supervisor mode and
can be accessed only by privileged instructions. The supervisor programming model consists of the
registers available in user mode as well as the registers listed in
1. These operations can be emulated via software functions.
1-6
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•
•
•
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31
No hardware support for MAC/EMAC and DIV instructions
Upward compatibility with all other ColdFire cores (V2–V5)
Debug visibility bus for real-time program tracing
16 general-purpose 32-bit registers (D0–D7, A0–A7)
32-bit program counter (PC)
8-bit condition code register (CCR)
V1 ColdFire Core
illustrates the integer portion of the user programming model. It consists of the following
User Programming Model
Supervisor Programming Model
20
MCF51AC256 ColdFire Integrated Microcontroller Reference Manual, Rev. 5
19
18
17
Figure 1-2. Supervisor Programming Model
Must be zeros
16
15
CCR
Chapter 7, “ColdFire Core.”
0
SR
OTHER_A7 Supervisor A7 stack pointer
VBR
CPUCR
Figure
Vector base register
CPU configuration register
Status register
1
1-2.
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