ATAR890-C_14 Datasheet, PDF (75/80 Pages) ATMEL Corporation – Up to 6 External/Internal Interrupt Sources

ATAR090-C/ATAR890-C
12. Emulation
The basic function of emulation is to test and evaluate the customer's program and hardware in
real time. This therefore enables the analysis of any timing, hardware or software problem. For
emulation purposes, all MARC4 controllers include a special emulation mode. In this mode, the
internal CPU core is inactive and the I/O buses are available via Port 0 and Port 1 to allow an
external access to the on-chip peripherals. The MARC4 emulator uses this mode to control the
peripherals of any MARC4 controller (target chip) and emulates the lost ports for the application.
The MARC4 emulator can stop and restart a program at specified points during execution, mak-
ing it possible for the applications engineer to view the memory contents and those of various
registers during program execution. The designer also gains the ability to analyze the executed
instruction sequences and all the I/O activities.
Figure 12-1. MARC4 Emulation
MARC4 emulator
Program
memory
MARC4
emulation-CPU
Trace
memory
CORE
Control
logic
Port 0 Port 1
Emulator target board
MARC4 target chip
I/O bus
I/O control
CORE
(inactive)
Emulation control
SYSCL/
TCL,
TE, NRST
Peripherals
Application-specific hardware
Personal computer
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4700C–4BMCU–02/05