Cycle Counter - Oki Dr.63514 User Manual

2.6.2 Cycle Counter

The 24-bit cycle counter tracks the machine cycles of each instruction executed as a yardstick to user
application program execution times.
Machine
cycle signal
Program counter
output
This counter offers three modes of operation.
• Count disabled
• Free-running count
• Trigger count
(1) Count disabled
No instructions are counted.
(2) Free-running count
Instructions are counted for all code memory addresses.
(3) Trigger count
All instructions between start and stop triggers based on code memory addresses are counted. There
are three possible trigger combinations:
a. Specifying both a start and stop address
Counting starts when real-time emulation visits the former and stops when the program counter
(PC) hits the latter.
b. Specifying a start address only
Counting starts when real-time emulation visits the former and continues until there is a break.
c. Specifying a stop address only
Counting starts simultaneously with real-time emulation and stops when the program counter
(PC) hits the latter.
Cycle count
signal
Cycle counter
control circuit
Figure 2-10 Cycle Counter
Chapter 2. Functions
Cycle counter
Cycle
overflow
counter
break request
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