Chapter 23 Memory Mapping Control (S12XMMCV2)
MC9S12XDP512 Data Sheet, Rev. 2.11
916 Freescale Semiconductor
23.5.3.4 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 1-30). When the ROMON bit is cleared, the application memory provides the data and
the emulator will observe the CPU internal actions (see Figure 1-31).
Figure 23-30. ROMON = 1 in Emulation Expanded Mode
EROMON = 1
Application
MCU
Flash
Memory
Emulator
EROMON = 0
Application
MCU
Memory
Emulator
Flash
Generator
Observer