MC68030 Datasheet, PDF (28/602 Pages) Motorola, Inc – ENHANCED 32-BIT MICROPROCESSOR

Introduction
Figure 1-2 shows the user programming model, consisting of 16 32-bit general-purpose reg-
isters and two control registers:
• General-Purpose 32-Bit Registers (D0–D7, A0–A7)
• 32-Bit Program Counter (PC)
• 8-Bit Condition Code Register (CCR)
The supervisor programming model consists of the registers available to the user plus 14
control registers:
• Two 32-Bit Supervisor Stack Pointers (ISP and MSP)
• 16-Bit Status Register (SR)
• 32-Bit Vector Base Register (VBR)
• 32-Bit Alternate Function Code Registers (SFC and DFC)
• 32-Bit Cache Control Register (CACR)
• 32-Bit Cache Address Register (CAAR)
• 64-Bit CPU Root Pointer (CRP)
• 64-Bit Supervisor Root Pointer (SRP)
• 32-Bit Translation Control Register (TC)
• 32-Bit Transparent Translation Registers (TT0 and TT1)
• 16-Bit MMU Status Register (MMUSR)
The user programming model remains unchanged from previous M68000 Family
microprocessors. The supervisor programming model supplements the user programming
model and is used exclusively by the MC68030 system programmers who utilize the
supervisor privilege level to implement sensitive operating system functions, I/O control, and
memory management subsystems. The supervisor programming model contains all the
controls to access and enable the special features of the MC68030. This segregation was
carefully planned so that all application software is written to run at the nonprivileged user
level and migrates to the MC68030 from any M68000 platform without modification. Since
system software is usually modified by system programmers when ported to a new design,
the control features are properly placed in the supervisor programming model. For example,
the transparent translation feature of the MC68030 is new to the family supervisor
programming model for the MC68030 and the two translation registers are new additions to
the family supervisor programming model for the MC68030. Only supervisor code uses this
feature, and user application programs remain unaffected.
MOTOROLA
MC68030 USER’S MANUAL
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