Q: What is the difference between SWD and JTAG debugging interfaces on STM32?
Answer
SWD (Serial Wire Debug) uses only two pins (SWDIO and SWCLK) compared to JTAG which requires five pins (TMS TCK TDO TDI and optional TRST). STM32 MCUs support both. SWD is preferred for space-constrained designs and is the default interface on most STM32 Cortex-M parts. JTAG is still useful when chain-debugging multiple devices or when boundary scan is needed. Both interfaces share the same SWDIO/SWCLK pins in SWD mode. On STM32CubeIDE the ST-Link debugger automatically detects which interface is available.
Related Articles
- h
- t
- t
- p
- s
- :
- /
- /
- i
- n
- n
- o
- v
- c
- h
- i
- p
- .
- n
- e
- t
- /
- h
- o
- w
- –
- t
- o
- –
- c
- h
- o
- o
- s
- e
- –
- t
- h
- e
- –
- r
- i
- g
- h
- t
- –
- s
- t
- m
- 3
- 2
- –
- m
- i
- c
- r
- o
- c
- o
- n
- t
- r
- o
- l
- l
- e
- r
- –
- f
- o
- r
- –
- y
- o
- u
- r
- –
- p
- r
- o
- j
- e
- c
- t
- /
Filed under: FAQ