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Applies to: DKR4
When I do the following:
DAP_WRITE_DPACC DPADDR 0x12345678
DAP_READ_DPACC DPADDR 0x12000070
The value being read through the DAP_READ_DPACC instruction is 0x03084013. I was expecting to read 0x12000070.
Can you explain where these register read/write addresses to or from?
The register which is referred to by DPADDR is actually known as the AP SELECT register in the
JTAG-DP: It is at address 0x8 when the Instruction Register (IR) contains DPACC, and is a
Register (table 6-2).
If you refer to this document, figure 6-4, you will find the bit assignments.
From Table 6-3 of the Debug interface spec doc, you can see that APSELECT register is a write only register and reading from that address (0x8), is actually reading RESEND register.
APSELECT register is write only and there is no way to read it back by SW-DP.
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