MC9S12XD256MAL Datasheet, PDF (647/1348 Pages) Freescale Semiconductor, Inc – Freescale’s Scalable Controller Area Network

Chapter 17 Memory Mapping Control (S12XMMCV2)
17.5.3.3 ROM Control in Normal Expanded Mode
In normal expanded mode the external bus will be connected to the application. If the ROMON bit is set,
the internal FLASH provides the data. If the ROMON bit is cleared, the application memory provides the
data (see Figure 1-29).
MCU
Application
Flash
MCU
Memory
ROMON = 1
Application
Memory
ROMON = 0
Figure 17-29. ROM in Normal Expanded Mode
MC9S12XDP512 Data Sheet, Rev. 2.21
Freescale Semiconductor
647