
C68000
16-bit Microprocessor
Megafunction
General Description
Features
Control Unit
16-bit two levels instruction decoder
Three levels instruction queue
The C68000 is megafunction of a powerful
16/32-bit microprocessor and is derived from the
Motorola MC68000 microprocessor. The C68000
is a fully functional 32-bit internal and 16-bit
external equivalent for the MC68000. The
C68000 serves interrupts and exceptions, and
provides an interface for M6800 family
peripherals.
55 instructions and 14 address modes
Supervisor and User mode
Independent stack for both modes
Users registers
Eight 32-bit data & address registers
16-bit status register
The C68000 is the microcode-free design
developed for reuse in ASIC and FPGA
implementations. The design is strictly
synchronous without internal tri-states and with a
synchronous reset
.
Data format
Integer 8, 16 or 32-bit
BCD packet
Bit
Symbol
Memory interface
Independent data and address buses
Asynchronous bus control
4 GB-address space
31-bit address bus (optional 32-bit)
8-address spaces (used 5)
16-bit data bus
C68000
fc
addr
clk
e
vma
vpa_n
berr_n
reseti_n
reseto_n
halti_n
halto_n
addrz
datai
datao
dataz
ctrlz
as_n
rw
uds_n
lds_n
dtack_n
br_n
bg_n
bgack_n
ipl_n
Interrupt Controller
Seven Priority Levels
Unlimited interrupt sources
Vectored or auto-vectored interrupt
modes
Arithmetic-Logic Unit
8, 16, 32-bit arithmetic and logic
operations
Boolean manipulations
16 x 16-bit multiplication (sign or
unsigned)
32 / 16-bit division (sign or unsigned)
M6800 peripherals family synchronous
interface
Two or Three wire bus arbitration interface
Operation execution is the same for data or
address registers
No different for operation on data or
address registers
CAST, Inc.
March 2004
Page 1