Freescale Semiconductor MCF5480 - Manual (Page 119)

Data Format Summary
MCF548x Reference Manual, Rev. 3
Freescale Semiconductor 3-15
3.4 Data Format Summary
Table 3-5 lists the operand data formats. Integer operands can reside in registers, memory, or instructions.
The operand size is either explicitly encoded in the instruction or implicitly defined by the instruction
operation.
3.4.1 Data Organization in Registers
The following sections describe data organization in data, address, and control registers. Section 6.2.2,
“Floating-Point Data Formats,” describes floating-point formatting.
3.4.1.1 Integer Data Format Organization in Registers
Figure 3-9 shows the integer format for data registers. Each integer data register is 32 bits wide. Byte and
word operands occupy the lower 8- and 16-bit portions of integer data registers, respectively. Longword
operands occupy the entire 32 bits of integer data registers. A data register that is either a source or
destination operand only uses or changes the appropriate lower 8 or 16 bits in byte or word operations,
respectively. The remaining high-order portion does not change. Note that the least-significant bit is bit 0
for all data types, whereas the msbs for longword integer is bit 31, the msb of a word integer is bit 15, and
the msb of a byte integer is bit 7.
FPL6 0x81D No 32 lsbs of floating-point data register 6
FPU7 0x81E No 32 msbs of floating-point data register 7
FPL7 0x81F No 32 lsbs of floating-point data register 7
FPIAR 0x821 No Floating-point instruction address register
FPSR 0x822 No Floating-point status register
FPCR 0x824 No Floating-point control register
Local Memory and Module Control Registers
RAMBAR0 0xC04 Yes RAM base address register 0
RAMBAR1 0xC05 Yes RAM base address register 1
MBAR 0xC0F Yes Primary module base address register (not a core
register)
Table 3-5. Integer Data Formats
Operand Data Format Size
Bit 1 bit
Byte integer 8 bits
Word integer 16 bits
Longword integer 32 bits
Table 3-4. ColdFire CPU Registers (Continued)
Name CPU Space (Rc) Written with MOVEC Register Name