2.7.7. APB-AP Banked Data Registers, BD0-BD3,
0x10-0x1C
BD0-BD3 provide a mechanism for directly mapping through DAP
accesses to APB transfers without having to rewrite the Transfer
Address Register within a four word boundary. For example, BD0 reads/write
from TAR, and BD1 from TAR+4.
Table 2.17 shows
the bit assignments.
Table 2.17. APB-AP Banked Data Registers bit assignments
| Bits | Type | Name | Function |
|---|
| [31:0] | R/W | Data | If DAPADDR[7:4] = 0x0001,
so accessing APB-AP registers in the range 0x10-0x1C,
then the derived PADDR[31:0] is: Write mode: Data value to write for the current
transfer to external address TAR[31:4] + DAPADDR[3:2] +
2'b00. Read mode: Data value read from the current transfer
from external address TAR[31:4] + DAPADDR[3:2] +
2'b00.
Auto address
incrementing is not performed on DAP accesses to BD0-BD3. Reset
value = 0x00000000 |
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