Chapter 23 Memory Mapping Control (S12XMMCV2)
MC9S12XDP512 Data Sheet, Rev. 2.11
Freescale Semiconductor 913
Due to internal visibility of CPU accesses the CPU will be halted during XGATE or BDM access to any
PRR. This rule applies also in normal modes to ensure that operation of the device is the same as in
emulation modes.
A summary of PRR accesses is the following:
An aligned word access to a PRR will take 2 bus cycles.
A misaligned word access to a PRRs will take 4 cycles. If one of the two bytes accessed by the
misaligned word access is not a PRR, the access will take only 3 cycles.
A byte access to a PRR will take 2 cycles.
Table 23-23. PRR Listing
PRR Name PRR Local Address PRR Location
PORTA $0000 PIM
PORTB $0001 PIM
DDRA $0002 PIM
DDRB $0003 PIM
PORTC $0004 PIM
PORTD $0005 PIM
DDRC $0006 PIM
DDRD $0007 PIM
PORTE $0008 PIM
DDRE $0009 PIM
MMCCTL0 $000A MMC
MODE $000B MMC
PUCR $000C PIM
RDRIV $000D PIM
EBICTL0 $000E EBI
EBICTL1 $000F EBI
Reserved $0012 MMC
MMCCTL1 $0013 MMC
ECLKCTL $001C PIM
Reserved $001D PIM
PORTK $0032 PIM
DDRK $0033 PIM