Datasheet

Background Debug Module (S12SBDMV1)
MC9S12G Family Reference Manual, Rev.1.23
Freescale Semiconductor 295
Figure 7-4. BDM CCR Holding Register (BDMCCR)
Read: All modes through BDM operation when not secured
Write: All modes through BDM operation when not secured
NOTE
When BDM is made active, the CPU stores the content of its CCR register
in the BDMCCR register. However, out of special single-chip reset, the
BDMCCR is set to 0xD8 and not 0xD0 which is the reset value of the CCR
register in this CPU mode. Out of reset in all other modes the BDMCCR
register is read zero.
When entering background debug mode, the BDM CCR holding register is used to save the condition code
register of the user’s program. It is also used for temporary storage in the standard BDM firmware mode.
The BDM CCR holding register can be written to modify the CCR value.
7.3.2.2 BDM Program Page Index Register (BDMPPR)
Figure 7-5. BDM Program Page Register (BDMPPR)
Read: All modes through BDM operation when not secured
Write: All modes through BDM operation when not secured
Register Global Address 0x3_FF06
7 6 5 4 3 2 1 0
R
CCR7 CCR6 CCR5 CCR4 CCR3 CCR2 CCR1 CCR0
W
Reset
Special Single-Chip Mode 1 1 0 0 1 0 0 0
All Other Modes 0 0 0 0 0 0 0 0
Register Global Address 0x3_FF08
7 6 5 4 3 2 1 0
R
BPAE
0 0 0
BPP3 BPP2 BPP1 BPP0
W
Reset 0 0 0 0 0 0 0 0
= Unimplemented, Reserved
Table 7-4. BDMPPR Field Descriptions
Field Description
7
BPAE
BDM Program Page Access Enable Bit — BPAE enables program page access for BDM hardware and
firmware read/write instructions The BDM hardware commands used to access the BDM registers (READ_BD
and WRITE_BD) can not be used for program page accesses even if the BPAE bit is set.
0 BDM Program Paging disabled
1 BDM Program Paging enabled
3–0
BPP[3:0]
BDM Program Page Index Bits 3–0 — These bits define the selected program page. For more detailed
information regarding the program page window scheme, please refer to the S12S_MMC Block Guide.