Datasheet

C167CS-4R
C167CS-L
Data Sheet 17 V2.2, 2001-08
Note: When one or both of the on-chip CAN Modules are used with the interface lines
assigned to Port 4, the CAN lines override the segment address lines and the
segment address output on Port 4 is therefore limited to 6/4 bits i.e. address lines
A21/A19 … A16. CS
lines can be used to increase the total amount of
addressable external memory.
Central Processing Unit (CPU)
The main core of the CPU consists of a 4-stage instruction pipeline, a 16-bit arithmetic
and logic unit (ALU) and dedicated SFRs. Additional hardware has been spent for a
separate multiply and divide unit, a bit-mask generator and a barrel shifter.
Based on these hardware provisions, most of the C167CS’s instructions can be
executed in just one machine cycle which requires 50 ns at 40 MHz CPU clock. For
example, shift and rotate instructions are always processed during one machine cycle
independent of the number of bits to be shifted. All multiple-cycle instructions have been
optimized so that they can be executed very fast as well: branches in 2 cycles, a 16
×
16 bit multiplication in 5 cycles and a 32-/16-bit division in 10 cycles. Another pipeline
optimization, the so-called ‘Jump Cache’, allows reducing the execution time of
repeatedly performed jumps in a loop from 2 cycles to 1 cycle.
Figure 4 CPU Block Diagram
MCB02147
CPU
SP
STKOV
STKUN
Instr. Reg.
Instr. Ptr.
Exec. Unit
4-Stage
Pipeline
MDH
MDL
PSW
SYSCON
Context Ptr.
Mul/Div-HW
R15
R0
General
Purpose
Registers
Bit-Mask Gen
Barrel - Shifter
ALU
(16-bit)
Data Page Ptr. Code Seg. Ptr.
Internal
RAM
R15
R0
ROM
16
16
32
BUSCON 0
BUSCON 1
BUSCON 2
BUSCON 3
BUSCON 4 ADDRSEL 4
ADDRSEL 3
ADDRSEL 2
ADDRSEL 1