Table 267. Debug Port Registers - ST STM32WL55JC Reference Manual

Debug support (DBG)
Bit 28 CDBGPWRUPREQ: control of DAPCLK enable request signal
0 = Requests DAPCLK gating
1 = Requests DAPCLK enabled
Bits 27:24 Reserved, must be kept at reset value.
Bits 23:12 TRNCNT[11:0]: transaction counter
To program a sequence of transactions to incremental addresses via an AP, TRNCNT is
loaded with the number of transactions to perform. It is decremented at the successful
completion of each transaction.
Bits 11:8 MASKLANE[3:0]: masked byte lanes
Indicates the bytes to be masked in pushed-compare and pushed-verify operations
(DP_CTRLSTATR.TRNMODE = 1 or 2). In the pushed operations, the word supplied in an
AP write transaction is compared with the current value at the target AP address.
1XXX = includes byte lane 3 in comparisons.
X1XX = includes byte lane 2 in comparisons.
XX1X = includes byte lane 1 in comparisons.
XXX1 = includes byte lane 0 in comparisons.
Bit 7 WDATAERR: write data error (read only) in SW-DP
There is a parity or framing error on the data phase of a write, or a write that has been
accepted by the DP is then discarded without being submitted to the AP.
This bit is reset by writing 1 to the DP_ABORTR.WDERRCLR bit.
0: No error
1: An error occurred.
Reserved in JTAG-DP.
Bit 6 READOK: AP read response (read only) in SW-DP
Indicates the response to the last AP read access.
0: Read not OK
1: Read OK
Reserved in JTAG-DP.
Bit 5 STICKYERR: transaction error (read only in SW-DP, R/W in JTAG-DP)
Indicates that an error occurred in an AP transaction.
0: No error
1: An error occurred.
In SW-DP, STICKYERR bit is read only, reset by writing 1 to the DP_ABORTR.STKERRCLR
bit.
In JTAG-DP, STICKYERR bit is read, cleared by writing a 1 to it.
Bit 4 STICKYCMP: match comparison (read only in SW-DP, R/W in JTAG-DP)
Indicates that a match occurred in a pushed operation.
0: match if TRNMODE = 0x1; no match if TRNMODE = 0x2
1: no match if TRNMODE = 0x1; match if TRNMODE = 0x2
In SW-DP, STICKYCMP bit is read only, reset by writing 1 to the DP_ABORTR.STKCMPCLR
bit.
In JTAG-DP, STICKYCMP bit is read, cleared by writing a 1 to it.
1328/1454 RM0453 Rev 2
RM0453