Si1000/1/2/3/4/5
8. CIP-51 Microcontroller
The MCU system controller core is the CIP-51 microcontroller. The CIP-51 is fully compatible with the
MCS-51™ instruction set; standard 803x/805x assemblers and compilers can be used to develop soft-
ware. The MCU family has a superset of all the peripherals included with a standard 8051. The CIP-51
also includes on-chip debug hardware (see description in Section 29), and interfaces directly with the ana-
log and digital subsystems providing a complete data acquisition or control-system solution in a single inte-
grated circuit.
The CIP-51 Microcontroller core implements the standard 8051 organization and peripherals as well as
additional custom peripherals and functions to extend its capability (see Figure 8.1 for a block diagram).
The CIP-51 includes the following features:
Fully Compatible with MCS-51 Instruction Set
25 MIPS Peak Throughput with 25 MHz Clock
0 to 25 MHz Clock Frequency
Reset Input
Power Management Modes
On-chip Debug Logic
Extended Interrupt Handler
Program and Data Memory Security
8.1. Performance
The CIP-51 employs a pipelined architecture that greatly increases its instruction throughput over the stan-
dard 8051 architecture. In a standard 8051, all instructions except for MUL and DIV take 12 or 24 system
clock cycles to execute, and usually have a maximum system clock of 12 MHz. By contrast, the CIP-51
core executes 70% of its instructions in one or two system clock cycles, with no instructions taking more
than eight system clock cycles.
DATA BUS
ACCUMULATOR
B
REGISTER
STACK POINTER
TMP1
TMP2
SRAM
ADDRESS
REGISTER
PSW
SRAM
ALU
DATA BUS
SFR_ADDRESS
SFR_CONTROL
BUFFER
D8
SFR
BUS
INTERFACE
D8
SFR_WRITE_DATA
SFR_READ_DATA
D8
DATA POINTER
PC INCREMENTER
D8
MEM_ADDRESS
MEM_CONTROL
PROGRAM COUNTER (PC)
PRGM. ADDRESS REG.
PIPELINE
MEMORY
INTERFACE
A16
D8
MEM_WRITE_DATA
MEM_READ_DATA
CONTROL
LOGIC
RESET
CLOCK
SYSTEM_IRQs
INTERRUPT
INTERFACE
EMULATION_IRQ
D8
STOP
IDLE
POWER CONTROL
REGISTER
D8
Figure 8.1. CIP-51 Block Diagram
Rev. 1.0
109
SILICON [ SILICON ]
