Справочник Пользователя для Freescale Semiconductor FRDM-KL25Z
FRDMKL25ZUM
FRDM-KL25Z User's Manual
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alternative device such as a 1.8V or 2.5V regulator. The KL25Z microcontroller has an
operating range of 1.71V to 3.6V.
2) J3 and J4 are not populated by default. The two pins of these headers are shorted
together by a trace on the bottom layer of the PCB. To measure the energy
consumption of either the KL25Z or the OpenSDA MCU, the trace between these pins
must first be cut. A current probe or a shunt resistor and voltage meter can then be
applied to measure the energy consumption on these rails.
operating range of 1.71V to 3.6V.
2) J3 and J4 are not populated by default. The two pins of these headers are shorted
together by a trace on the bottom layer of the PCB. To measure the energy
consumption of either the KL25Z or the OpenSDA MCU, the trace between these pins
must first be cut. A current probe or a shunt resistor and voltage meter can then be
applied to measure the energy consumption on these rails.
5.2 Serial and Debug Adapter (OpenSDA)
OpenSDA is an open-standard serial and debug adapter. It bridges serial and debug communications
between a USB host and an embedded target processor as shown in Figure 4. The hardware circuit is
based on a Freescale Kinetis K20 family microcontroller (MCU) with 128 KB of embedded flash and an
integrated USB controller. OpenSDA features a mass storage device (MSD) bootloader, which provides
a quick and easy mechanism for loading different OpenSDA Applications such as flash programmers,
run-control debug interfaces, serial-to-USB converters, and more. Refer to the OpenSDA User’s Guide
for more details.
between a USB host and an embedded target processor as shown in Figure 4. The hardware circuit is
based on a Freescale Kinetis K20 family microcontroller (MCU) with 128 KB of embedded flash and an
integrated USB controller. OpenSDA features a mass storage device (MSD) bootloader, which provides
a quick and easy mechanism for loading different OpenSDA Applications such as flash programmers,
run-control debug interfaces, serial-to-USB converters, and more. Refer to the OpenSDA User’s Guide
for more details.
Figure 4. OpenSDA High-Level Block Diagram
OpenSDA is managed by a Kinetis K20 MCU built on the ARM® Cortex™-M4 core. The OpenSDA circuit
includes a status LED (D4) and a pushbutton (SW1). The pushbutton asserts the Reset signal to the
KL25Z target MCU. It can also be used to place the OpenSDA circuit into Bootloader mode. SPI and
GPIO signals provide an interface to either the SWD debug port of the KL25Z. Additionally, signal
connections are available to implement a UART serial channel. The OpenSDA circuit receives power
when the USB connector J7 is plugged into a USB host.
includes a status LED (D4) and a pushbutton (SW1). The pushbutton asserts the Reset signal to the
KL25Z target MCU. It can also be used to place the OpenSDA circuit into Bootloader mode. SPI and
GPIO signals provide an interface to either the SWD debug port of the KL25Z. Additionally, signal
connections are available to implement a UART serial channel. The OpenSDA circuit receives power
when the USB connector J7 is plugged into a USB host.
5.2.1 Debug Interface
Signals with SPI and GPIO capability are used to connect directly to the SWD of the KL25Z. These
signals are also brought out to a standard 10-pin (0.05”) Cortex Debug connector (J6). It is possible to
isolate the KL25Z MCU from the OpenSDA circuit and use J6 to connect to an off-board MCU. To
Signals with SPI and GPIO capability are used to connect directly to the SWD of the KL25Z. These
signals are also brought out to a standard 10-pin (0.05”) Cortex Debug connector (J6). It is possible to
isolate the KL25Z MCU from the OpenSDA circuit and use J6 to connect to an off-board MCU. To