Real-Time Tracing - Oki Dr.63514 User Manual

2.5 Real-time Tracing

Real-time tracing stores the current instruction address, the contents of ACC and other registers, flag
states, etc. for post mortem analysis of real-time emulation.
The emulator uses the 13-bit trace pointer to keep track of the location of the next entry to be written
within its 8192-entry trace table. When the trace pointer reaches that number, it recycles, overwriting the
oldest entry first.
Trace enable bits
Program
counter
output
Trace control circuit
For each code memory address, the emulator provides a trace enable bit for use in limiting tracing to
specific addresses.
Code memory
0000H
0001H
0002H
0003H
0004H
0FFFDH
0FFFEH
0FFFFH
Trace
signal
Trace pointer
(13-bit counter)
Figure 2-7 Real-Time Tracing
Trace enable bits
Address specified by
program counter (PC)
To trace control circuit
Figure 2-8 Trace Enable Bits
Chapter 2. Functions
Trace data
0
1
2
3
4
8190
8191
Trace memory
(Overflow signal) Trace
memory full
break request
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