The board has been received, so I can only say that the express desk is not strong enough. The board was put in the guard, but I didn't tell him about it until I called.

The packaging is very good and the workmanship is quite solid.

As we all know, the Freedom development board is an important development platform for Freescale to lay out ARM Cortex-M series microcontrollers. The boards of this platform have similar characteristics, such as based on the Kinetics series MCU, equipped with Freescale sensors, equipped with OpenSDA debugging interface, and compatible with Arduino? R3 expansion interface and other characteristics, it is a small, low-power, cost-effective microcontroller evaluation and development platform. As long as the engineer has played one of them, he can also easily grasp other series of boards on the Freedom platform. This is the so-called ecosystem advantage. However, the problem comes again. Since the boards are so similar, what major innovation will FRDM-K64F have?

The answer is OpenSDAv2. On the development board of FRDM-KL25Z, we first came into contact with Freescale's cross epochal onboard OpenSDA debugger. It uses the USB flash disk Device mode to write code, eliminating the need to install additional debugger drivers, and its firmware update and stability are commendable. OpenSDA debugger not only facilitates the establishment of the entire development platform, but also provides a variety of serial communication, Flash programming and debugging operation methods, which allows engineers to evaluate and develop Freescale Kinetics series microcontrollers conveniently and quickly without increasing research and development costs (OpenSDA debugger).

However, the first generation OpenSDA is not as "Open" as its name suggests. It is not open source. However, with the development of the FRDM-K64F development board, OpenSDA has also been upgraded from the first generation to OpenSDA V2. The hardware circuit has also been slightly changed. The logic of level conversion has been added, and 2.5V, 1.8V and other levels can also be used, which is suitable for some more high-end MCU, The firmware of OpenSDA V2 has been completely replaced by the open source CMSIS-DAP debugger, which solves the open source problem including Bootloader and all applications (Debug, virtual serial port, MSD, etc.), which can be said to be an important milestone of the FRDM-K64F development board.

In addition, the firmware and application file format of OpenSDA V2 have become more unified, becoming the. bin file format instead of the original one S19,. SDA format, and it must be noted that the downloaded code cannot be run if confused.

After learning about the significant improvement of the FRDM-K64F development board to OpenSDA V2, let's look back and see if this development board has a much higher image.

You still remember the meeting when Freescale development board was just launched. The compact and round shape is impressive. Freescale, as always, adopts this style on all Freedom platforms, which is very interesting. The FRDM-K64F development board is designed as a 4-layer board, which is smaller than common business cards. Some resources on the board are shown in the following figure:

FRDM-K64F Development Board Features:

• MK64FN1M0VLL12 MCU (120 MHz, 1 MB flash memory, 256 KB RAM, low power consumption, amorphous USB and 100 pin thin quad flat pack (LQFP))

• Dual purpose USB interface with Micro-B USB connector

•         RGB LED

• FXOS8700CQ Accelerometer and Magnetometer

• Two user buttons

• Flexible power supply options - OpenSDAv2 USB, Kinetics K64 USB and external power

• Arduino? Compatible? I/O connector of R3 provides easy access to MCU I/O

• The programmable OpenSDAv2 debugging circuit supports CMSIS-DAP interface software and provides the following functions:

• Ethernet, SDHC interface

• Additional RF module: nRF24L01+Nordic 2.4GHz radio

• Additional Bluetooth module: JY-MCU BT circuit board V1.05 BT

OpenSDA v2：

• Mass Storage Device (MSD) flash programming interface

• CMSIS-DAP debugging interface can provide operation control debugging function through drive free USB HID connection, compatible with IDE tools

• Virtual serial port

• Open source CMSIS-DAP software project

From the onboard resources of the FRDM-K64F, the functions are very rich. First, is the board hardware compatible with Arduino? R3 expansion interface provides a wealth of expansion module options. In addition, the board carries a wealth of peripherals, including 6-axis digital accelerometer and magnetometer for developing complete electronic compass functions, 3-color LED for direct interaction and feedback and two user buttons, memory that can be expanded through microSD card slot, and on-board 10/100M Ethernet port, Connection options such as connectors for Bluetooth and 2.4 GHz radio add ons enable rapid prototyping.

Microcontroller MK64FN1M0VLL12

FRDM-K64F development board is equipped with Freescale Kinetics K64 series microcontroller MK64FN1M0VLL12120MHz main frequency, based on Cortex-M4F processor, supporting IEEE 1588 Ethernet, suitable for applications requiring high memory density, low power consumption and high processing efficiency. This series supports the crystal free USB design, which can reduce system costs and save circuit board space. It also has the comprehensive support tools and scalability inherent in the Kinetics product portfolio.

MK64FN1M0VLL12 microcontroller characteristics:

• ARM Cortex-M4 core, 120 main frequency, DSP instruction+FPU unit

• 1MB Flash、256KB  SRAM、 FlexMemory

• Two 16 bit SAR ADC, two 12 bit DAC, three analog comparators, reference voltage

• Ethernet controller with MII and RMII interfaces, USB full speed/low speed local controller, controller area network (CAN) module

• Three SPI modules, three I2C modules, supporting up to 1 Mbit/s, six UART modules, SDHC interfaces, and I2S modules

Looking back at Freescale Kinetics K series, we can see that the microcontroller MK64FN1M0VLL12 is mainly oriented to applications that need Ethernet, CAN communication and USB functions, as shown in the figure below.

Power on and development of FRDM-K64F development board

The development process of FRDM-K64 development board is roughly the same as that of other series of boards on Freedom platform. I won't repeat it here. For details, please refer to the following evaluation article.

• Support crystal free USB design -- Freescale FRDM-K22F evaluation

• The latest Freedom development platform FRDM-KE02Z -- 8-bit computer terminator

• Freescale development platform FRDM-KE02Z follow-up - perfect attack

• Freescale Ultra Low Cost Development Board Evaluation (I)

• Freescale Ultra Low Cost Development Board Evaluation (II)

However, it is worth mentioning that the FRDM-K64F development board supports the ARM mbed project. Currently, Freescale platform supports the ARM mbed project, including FRDM-KL25Z FRDM-KL05Z, FRDM-KL46Z, FRDM-K64F, and FRDM-K22F (as shown in the figure below). All boards have been evaluated. From the comparison, we can see that FRDM-K64F is a development board with very high configuration specifications in the Freedom platform and supports the ARM mbed project.

We can see the USB storage disk of ARM mbed project on the PC side.

For example, when loading the wdog_demo.bin file, we can check through the serial port that the door timer has been running circularly, unless reset by pressing the reset key or SW2 key.

More routines will not be demonstrated one by one in this article. Friends who want to try can apply for a play in Freescale Community.

Summary

This paper introduces another major change of the development board FRDM-K64F under Freedom platform, the onboard high-performance Cortex-M4 core based microcontroller Kinetics K64, the fully open source OpenSDA second generation debugger, Ethernet functions The CAN communication interface, 6-axis digital accelerometer and magnetometer are a platform that can help engineers quickly achieve prototype design. At present, there are free activities in Freescale community, and you can go to see what you like.