Datasheet

Chapter 16 Debug Module (DBGV1)
MC9S12E128 Data Sheet, Rev. 1.07
Freescale Semiconductor 485
16.3.2.5 Debug Comparator C Extended Register (DBGCCX)
76543210
R
PAGSEL EXTCMP
W
Reset 0 0 0 00000
Figure 16-9. Debug Comparator C Extended Register (DBGCCX)
Table 16-10. DBGCCX Field Descriptions
Field Description
7:6
PAGSEL
Page Selector Field — In both BKP and DBG mode, PAGSEL selects the type of paging as shown in
Table 16-11.
DPAGE and EPAGE are not yet implemented so the value in bit 7 will be ignored (i.e., PAGSEL values of 10 and
11 will be interpreted as values of 00 and 01, respectively).
5:0
EXTCMP
Comparator C Extended Compare Bits — The EXTCMP bits are used as comparison address bits as shown
in Table 16-11 along with the appropriate PPAGE, DPAGE, or EPAGE signal from the core.
Note: Comparator C can be used when the DBG module is configured for BKP mode. Extended addressing
comparisons for comparator C use PAGSEL and will operate differently to the way that comparator A and
B operate in BKP mode.
Table 16-11. PAGSEL Decoding
1
1
See Figure 16-10.
PAGSEL Description EXTCMP Comment
00 Normal (64k) Not used No paged memory
01 PPAGE
(256 — 16K pages)
EXTCMP[5:0] is compared to
address bits [21:16]
2
2
Current HCS12 implementations have PPAGE limited to 6 bits. Therefore, EXTCMP[5:4] should be set to 00.
PPAGE[7:0] / XAB[21:14] becomes
address bits [21:14]
1
10
3
3
Data page (DPAGE) and Extra page (EPAGE) are reserved for implementation on devices that support paged data and extra
space.
DPAGE (reserved)
(256 — 4K pages)
EXTCMP[3:0] is compared to
address bits [19:16]
DPAGE / XAB[21:14] becomes address
bits [19:12]
11
2
EPAGE (reserved)
(256 — 1K pages)
EXTCMP[1:0] is compared to
address bits [17:16]
EPAGE / XAB[21:14] becomes address
bits [17:10]