Serial Wire Debug (SWD) is a 2-pin electrical alternative JTAG interface that has the same JTAG protocol on top.

learn more… | top users | synonyms

2
votes
0answers
15 views

Interesting reset pin activity on Freescale Kinetis KL26 microcontroller

I just assembled a board that I have created that basically acts as a breakout board for a MKL26Z32VFM4. Today, I am trying to get it to communicate over SWD so I can program the initial bootloader. ...
2
votes
1answer
152 views

How can I design my PCB in a way I can debug the Atmel microcontroller on board?

We are designing a board around Atmel SAM4E microcontroller, and use Atmel-ICE for debugging/programming. To save space, we would like to avoid including the whole ICE connector. Which are the minimum ...
2
votes
1answer
90 views

How do I print debug messages to gdb console with STM32 discovery board using GDB, OpenOCD and arm-none-eabi-gcc?

I'm programming an STM32 Cortex M0 discovery board (32F0308DISCOVERY) using OpenOCD, arm-none-eabi-gcc, and gdb. I was wondering if there is any straightforward way to log debug messages over SWD. ...
0
votes
0answers
24 views

MCU Debugging: What is the difference between ITM, SWV and Trace?

What is the difference between ITM (Instrumentation Trace Macrocell), SWV (serial wire viewer) and Trace? For example, in an Atmel SAMG53 ARM M4F; it supports: ...
1
vote
3answers
239 views

Can you safely “short circuit” 2 signals when they compete for the same pin to avoid having to use a multiplexer?

I'm developing for a very limited, 8 pin LPC810 microcontroller and have to connect multiple signals on a single pin. Obviously, if there's only 1 output signal on a bus, that should be OK, but what ...
2
votes
1answer
107 views

SWD and i2C hardware layer differences

Both I2C and SWD are two-wire protocols. I wonder what are the main differences of the hardware layer of these protocols and what are the pros/cons of each one? It's also interesting that the maximum ...
1
vote
0answers
532 views

STM32 - two errors in turns during programming

I'm trying to program STM32F107VCT6 via SWD and I'm constantly getting two errors in turns (literally): Error: Connect failed, check config and cable connection ...
1
vote
1answer
314 views

How to daisy chain SWD Debug port

I have multiple mcu's that are configured to communicate with bus topology. I have 10 pins (4 of them is occupied by now) I need to debug (update firmware online, etc) all of these mcu's. I read this ...
1
vote
1answer
131 views

JTAG/SWD Data Logging

I would like to automatically poll and log certain memory locations on the STM32 I'm working with through the j-link debugger I am using to debug the system. Is this possible through the JTAG or SWD ...
3
votes
0answers
206 views

OpenOCD w/ ARM-USB-OCD-H+ARM_JTAG_SWD

Has anyone been able to debug/program using SWD over a Olimex USB-JTAG programmer and the ARM-JTAG-SWD adapter? If so, please share how you did it :) Specifically, I'm looking for what the OpenOCD ...
2
votes
0answers
203 views

Relationship between reset pins and SWD functions (ARM Cortex M0)

On many microcontrollers or other devices without JTAG/SWD functionality, there is a reset pin which when low unconditionally and asynchronously forces everything into a known state. On devices with ...
2
votes
3answers
2k views

Laying out a 10-pin JTAG/SWD connector on a final design

I'm designing a board with an ARM microcontroller on it (LPC1347FBD48) and I want to include a 10 pin jtag/swd connector, as is standard, for in-circuit debugging of my final design. Here is the ...
1
vote
0answers
235 views

JLNINK(SWD)+IAR can not debug stm32: communication error

guys. I am using J-link with SWD interface to debug my STM32F103VCT6 in IAR. I can enter download and debug mode but I can not use "step over" or "stop" function. Once I use one of them I will get ...
5
votes
2answers
4k views

JTAG vs SWD debugging

Skimming through this article I'm just wondering, what are the benefits of SWD debugging over JTAG debugging? I understand SWD uses less wires/pins, takes up less space etc. But how does it play out ...
2
votes
2answers
407 views

Finding an affordable integrated USB MCU [on hold]

I'm in the early stages of designing a development board around Cypress Semiconductor's PSoC 3 and 5 range of chips. Much like the Arduino, I'd like the programming experience to be very easy, and ...
2
votes
3answers
520 views

SWD debugging solution

I'm planning to start a project based around a Freescale Cortex-M0+ chip. Apparently the M0+ is SWD only and does not support JTAG. I've been looking around, but I can't find much in the way of SWD ...
1
vote
1answer
238 views

generating a custom half duplex 1 wire serial protocal

I want to use a microcontroller from NXP to generate a SWD (Serial wire debug) serial signal. A SWD signal is a clock and a host to target header, a single cycle wait period, followed by either a host ...
2
votes
2answers
164 views

Debugging STM32LF1xx low-power behavior

Is there any practical way to use a SWD-based debugger such as those made by Segger to debug a program for the STM32LF1xx which uses low-power modes and sets the clock speed very slow? The debugger ...