ST STM32L0x3 User Manual

Debug support (DBG) RM0367
962/1043 RM0367 Rev 7
33.5.6 SW-AP registers
Access to these registers are initiated when APnDP=1
There are many AP Registers addressed as the combination of:
• The shifted value A[3:2]
• The current value of the DP SELECT register.
10 Write SELECT
The purpose is to select the current access
port and the active 4-words register window
11 Read/Write READ BUFFER
This read buffer is useful because AP
accesses are posted (the result of a read AP
request is available on the next AP
transaction).
This read buffer captures data from the AP,
presented as the result of a previous read,
without initiating a new transaction
Table 177. SW-DP registers (continued)
A[3:2] R/W
CTRLSEL bit
of SELECT
register
Register Notes
Table 178. 32-bit debug port registers addressed through the shifted value A[3:2]
Address A[3:2] value Description
0x0 00 Reserved, must be kept at reset value.
0x4 01
DP CTRL/STAT register. Used to:
– Request a system or debug power-up
– Configure the transfer operation for AP accesses
– Control the pushed compare and pushed verify operations.
– Read some status flags (overrun, power-up acknowledges)
0x8 10
DP SELECT register: Used to select the current access port and the
active 4-words register window.
– Bits 31:24: APSEL: select the current AP
– Bits 23:8: reserved
– Bits 7:4: APBANKSEL: select the active 4-words register window on the
current AP
– Bits 3:0: reserved
0xC 11
DP RDBUFF register: Used to allow the debugger to get the final result
after a sequence of operations (without requesting new JTAG-DP
operation)

ST STM32L0x3 Specifications

General

Brand	ST
Model	STM32L0x3
Category	Microcontrollers
Language	English