What is a JTAG connector?
A JTAG interface is a special interface added to a chip. Depending on the version of JTAG, two, four, or five pins are added. The four and five pin interfaces are designed so that multiple chips on a board can have their JTAG lines daisy-chained together if specific conditions are met.
What is JTAG interface used for?
Using a simple four-pin interface, JTAG / boundary scan allows the signals on enabled devices to be controlled and monitored without any direct physical access.
What are SWD pins?
In SWD mode, two pins are used for debugging: one bi-directional pin (SWDIO) transfers the information and the second pin (SWDCLK) clocks the data. A third pin (SWO) delivers the trace data at minimum system cost. The Serial Wire and JTAG pins are shared.
Is St link a JTAG?
Description. The ST-LINK/V2 is an in-circuit debugger and programmer for the STM8 and STM32 microcontrollers. The single-wire interface module (SWIM) and JTAG/serial wire debugging (SWD) interfaces are used to communicate with any STM8 or STM32 microcontroller located on an application board.
What is JTAG TAP?
The JTAG interface, collectively known as a Test Access Port, or TAP, uses the following signals to support the operation of boundary scan. TCK (Test Clock) – this signal synchronizes the internal state machine operations.
How do you use a Nucleo as a ST Link?
Use a standard Nucleo board which includes an ST-Link interface. Do the following to connect the Nucleo board to the target (see figure of Nucleo board below): Open JP6 jumper (3.3 V power of the Nucleo MCU, to avoid MCU signals) Solder in JP4 pin header (not factory fitted)
What is JTAG daisy chain?
The JTAG specification introduced daisy chaining of MCUs in order to reduce the number of headers required to debug and program multiple MCUs. JTAG daisy chaining allows multiple MCU’s (and other JTAG compatible hardware, such as FPGAs) to share a single debug header.