What is Address 0xE00FFxxx?

[IYah]

Hi,

I am studying SWD and I hooked up a Logic Analyzer to see the data sent over the SWD wires. The board that I use is Nucleo 64 with STM32F030.

First, ST-Link requested a Debug Base Adress and target board returned 0xE00FF003 (BASE is 0xE00FF000). Then I saw ST-Link sent a read request at address 0xE00FFFE4, then 0xE00FFFE8, and target board returned something not error.

I've searched all the documents I could find (datasheet, programming guide, reference manual...) and internal search, could not find any info on these addresses. Does anybody know what these registers are and where the documents are? Thanks

[waclawek.jan]

ARM® v7-M Architecture Reference Manual:

 ARM reserves the first 1MB of this system address space, 0xE0000000 to 0xE00FFFFF , as the Private Peripheral Bus (PPB).

0xE00FF000 - 0xE00FFFFF ROM table

C1.2.2 The ARMv7-M ROM Table

offset content

0xFF0 0x0000000D CID0

0xFF4 0x00000010 CID1

0xFF8 0x00000005 CID2

0xFFC 0x000000B1 CID3