S912XHZ512F1VAG Datasheet, PDF (888/978 Pages) Freescale Semiconductor, Inc – Covers MC9S12XHZ384, MC9S12XHZ256

Chapter 25 Memory Mapping Control (S12XMMCV3)
25.5.3.4 ROM Control in Emulation Expanded Mode
In emulation expanded mode the external bus will be connected to the emulator and to the application. If
the ROMON bit is set, the internal FLASH provides the data. If the EROMON bit is set as well the
emulator observes all CPU internal actions, otherwise the emulator provides the data and traces all CPU
actions (see Figure 25-30). When the ROMON bit is cleared, the application memory provides the data
and the emulator will observe the CPU internal actions (see Figure 25-31).
MCU
Emulator
Observer
Flash
Application
MCU
Memory
EROMON = 1
Emulator
Generator
Flash
Application
Memory
EROMON = 0
Figure 25-30. ROMON = 1 in Emulation Expanded Mode
MC9S12XHZ512 Data Sheet, Rev. 1.06
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