ST STM32L4 5 Series User Manual

DocID024597 Rev 5 1801/1830
RM0351 Debug support (DBG)
1807
TPUI TRACE pin assignment
By default, these pins are NOT assigned. They can be assigned by setting the
TRACE_IOEN and TRACE_MODE bits in the Debug MCU configuration register
(DBGMCU_CR). This configuration has to be done by the debugger host.
In addition, the number of pins to assign depends on the trace configuration (asynchronous
or synchronous).
• Asynchronous mode: 1 extra pin is needed
• Synchronous mode: from 2 to 5 extra pins are needed depending on the size of the
data trace port register (1, 2 or 4) :
– TRACECK
– TRACED(0) if port size is configured to 1, 2 or 4
– TRACED(1) if port size is configured to 2 or 4
– TRACED(2) if port size is configured to 4
– TRACED(3) if port size is configured to 4
To assign the TRACE pin, the debugger host must program the bits TRACE_IOEN and
TRACE_MODE[1:0] of the Debug MCU configuration register (DBGMCU_CR). By default
the TRACE pins are not assigned.
This register is mapped on the external PPB and is reset by the PORESET (and not by the
SYSTEM reset). It can be written by the debugger under SYSTEM reset.
Table 323. Synchronous TRACE pin assignment
TPUI pin name
Trace synchronous mode TM32L4x5/
STM32L4x6 pin
assignment
Type Description
TRACECK O TRACE Clock PE2
TRACED[3:0] O
TRACE Synchronous Data Outputs
Can be 1, 2 or 4.
PE[6:3]
PC1, PC8, PD2,
PC12
(1)
1. PC1, PC8, PD2, PC12 only for STM32L496xx/4A6xx devices
Table 324. Flexible TRACE pin assignment
DBGMCU_CR
register
Pins
assigned for:
TRACE IO pin assigned
TRACE
_IOEN
TRACE
_MODE
[1:0]
PB3 / JTDO/
TRACESWO
PE2 /
TRACECK
PE3 or
PC1
(1)
/
TRACED[0]
PE4 or
PC8
(1)
/
TRACED[1]
PE5 or
PD2
(1)
/
TRACED[2]
PE6 or
PC12
(1)
/
TRACED[3]
0XX
No Trace
(default state)
Released
(2)
-
100
Asynchronous
Trace
TRACESWO
- -
Released
(usable as GPIO)

ST STM32L4 5 Series Specifications

General

Brand	ST
Model	STM32L4 5 Series
Category	Microcontrollers
Language	English