MC68HC000RC12 Datasheet, PDF (17/189 Pages) Freescale Semiconductor, Inc – 8-/16-/32-Bit Microprocessors User’s Manual

Freescale Semiconductor, Inc.
tables. The SFC and DFC registers allow the supervisor to access user data space or
emulate CPU space cycles.
31
16 15
0
A7' SUPERVISOR STACK
(SSP) POINTER
15
87
0
CCR
SR STATUS REGISTER
31
0
VBR VECTOR BASE REGISTER
20
SFC _{ALTERNATE FUNCTION}
DFC ^{CODE REGISTERS}
Figure 2-3. Supervisor Programmer's Model Supplement
(MC68010)
2.1.3 Status Register
The status register (SR),contains the interrupt mask (eight levels available) and the
following condition codes: overflow (V), zero (Z), negative (N), carry (C), and extend (X).
Additional status bits indicate that the processor is in the trace (T) mode and/or in the
supervisor (S) state (see Figure 2-4). Bits 5, 6, 7, 11, 12, and 14 are undefined and
reserved for future expansion
SYSTEM BYTE
USER BYTE
TRACE MODE
SUPERVISOR
STATE
INTERRUPT
MASK
15
13
T
S
10 8
I2 I1 I0
4
0
X N ZV C
EXTEND
NEGATIVE
ZERO
OVERFLOW
CARRY
CONDITION
CODES
Figure 2-4. Status Register
2.2 DATA TYPES AND ADDRESSING MODES
The five basic data types supported are as follows:
1. Bits
2. Binary-Coded-Decimal (BCD) Digits (4 Bits)
3. Bytes (8 Bits)
4. Words (16 Bits)
5. Long Words (32 Bits)
MOTOROLA
M68000 8-/16-/32-BIT MICROPROCESSOR USER’S MANUAL
2-3
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