Freescale Semiconductor MC9S12ZVM series, Справочное руководство

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Chapter 5 Background Debug Controller (S12ZBDCV2)
MC9S12ZVM Family Reference Manual Rev. 1.3
Freescale Semiconductor 171
Table 5-10. Field Location to Byte Access Mapping
5.4.5.2.1 FILL_MEM and DUMP_MEM Increments and Alignment
FILL_MEM and DUMP_MEM increment the previously accessed address by the previous access size to
calculate the address of the current access. On misaligned longword accesses, the address bits [1:0] are
forced to zero, therefore the following FILL_MEM or DUMP_MEM increment to the first address in the
next 4-byte field. This is shown in
Table 5-11 , the address of the first DUMP_MEM.32 following
READ_MEM.32 being calculated from 04.
When misaligned word accesses are realigned, then the original address (not the realigned address) is
incremented for the following FILL_MEM, DUMP_MEM command.
Misaligned word accesses can cause the same locations to be read twice as shown in rows 6 and 7. The
hardware ensures alignment at an attempted misaligned word access across a 4-byte boundary, as shown
in row 7. The following word access in row 8 continues from the realigned address of row 7.
d
Address[1:0] Access Size 00 01 10 11 Note
00 32-bit Data[31:24] Data[23:16] Data [15:8] Data [7:0]
01 32-bit Data[31:24] Data[23:16] Data [15:8] Data [7:0] Realigned
10 32-bit Data[31:24] Data[23:16] Data [15:8] Data [7:0] Realigned
11 32-bit Data[31:24] Data[23:16] Data [15:8] Data [7:0] Realigned
00 16-bit Data [15:8] Data [7:0]
01 16-bit Data [15:8] Data [7:0]
10 16-bit Data [15:8] Data [7:0]
11 16-bit Data [15:8] Data [7:0] Realigned
00 8-bit Data [7:0]
01 8-bit Data [7:0]
10 8-bit Data [7:0]
11 8-bit Data [7:0]
Denotes byte that is not transmitted
Table 5-11. Consecutive Accesses With Variable Size
Row Command Address Address[1:0] 00 01 10 11
1 READ_MEM.32 0x004003 11 Accessed Accessed Accessed Accessed
2 DUMP_MEM.32 0x004004 00 Accessed Accessed Accessed Accessed
3 DUMP_MEM.16 0x004008 00 Accessed Accessed
4 DUMP_MEM.16 0x00400A 10 Accessed Accessed
5 DUMP_MEM.08 0x00400C 00 Accessed
6 DUMP_MEM.16 0x00400D 01 Accessed Accessed
7 DUMP_MEM.16 0x00400E 10 Accessed Accessed
8 DUMP_MEM.16 0x004010 01 Accessed Accessed