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MCF5272 User’s Manual
Programming Model
2.2.1.6 MAC Programming Model
Figure 2-3 shows the registers in the MAC portion of the user programming model. These
registers are described as follows:
•
Accumulator (ACC)—This 32-bit, read/write, general-purpose register is used to
accumulate the results of MAC operations.
•
Mask register (MASK)—This 16-bit general-purpose register provides an optional
address mask for MAC instructions that fetch operands from memory. It is useful in
the implementation of circular queues in operand memory.
•
MAC status register (MACSR)—This 8-bit register defines configuration of the
MAC unit and contains indicator flags affected by MAC instructions. Unless noted
otherwise, MACSR indicator flag settings are based on the final result, that is, the
result of the final operation involving the product and accumulator.
2.2.2 Supervisor Programming Model
The MCF5272 supervisor programming model is shown in Figure 2-3. Typically, system
programmers use the supervisor programming model to implement operating system
functions and provide memory and I/O control. The supervisor programming model
provides access to the user registers and additional supervisor registers, which include the
upper byte of the status register (SR), the vector base register (VBR), and registers for
configuring attributes of the address space connected to the Version 2 processor core. Most
supervisor-mode registers are accessed by using the MOVEC instruction with the control
register definitions in Table 2-2.
2.2.2.1 Status Register (SR)
The SR stores the processor status, the interrupt priority mask, and other control bits.
Supervisor software can read or write the entire SR; user software can read or write only
SR[7–0], described in Section 2.2.1.5, “Condition Code Register (CCR).” The control bits
indicate processor states—trace mode (T), supervisor or user mode (S), and master or
interrupt state (M). SR is set to 0x27xx after reset.
Table 2-2. MOVEC Register Map
Rc[11–0]
Register Definition
0x002
Cache control register (CACR)
0x004
Access control register 0 (ACR0)
0x005
Access control register 1 (ACR1)
0x801
Vector base register (VBR)
0xC00
ROM base address register
0xC04
RAM base address register (RAMBAR)
0xC0F
Module base address register (MBAR)
Summary of Contents for DigitalDNA ColdFire MCF5272
Page 1: ...MCF5272UM D Rev 0 02 2001 MCF5272 ColdFire Integrated Microprocessor User s Manual ...
Page 38: ...xxxviii MCF5272 User s Manual TABLES Table Number Title Page Number ...
Page 58: ...1 10 MCF5272 User s Manual MCF5272 Specific Features ...
Page 90: ...2 42 MCF5272 User s Manual Exception Processing Overview ...
Page 96: ...3 6 MCF5272 User s Manual MAC Instruction Execution Timings ...
Page 158: ...5 46 MCF5272 User s Manual Motorola Recommended BDM Pinout ...
Page 184: ...7 12 MCF5272 User s Manual Interrupt Controller Registers ...
Page 338: ...13 44 MCF5272 User s Manual Application Examples ...
Page 414: ...18 6 MCF5272 User s Manual PWM Programming Model ...
Page 452: ...19 38 MCF5272 User s Manual Power Supply Pins ...
Page 482: ...20 30 MCF5272 User s Manual Reset Operation ...
Page 492: ...21 10 MCF5272 User s Manual Non IEEE 1149 1 Operation ...