I summary

         FRDM-K64F It is an ultra low-cost development platform for Kinetis K64 、 K63 and K24 MCU 。 FRDM-K64F 's hardware specifications are compatible Arduino ™ R3 The pin layout provides a wealth of expansion board options. FRDM-K64F Equipped with a variety of peripherals, including six Axis digital accelerometer and magnetometer for direct interaction and feedback three colour LED And two user buttons microSD Memory for card slot expansion, and onboard Ethernet port for Bluetooth and 2.4 GHz Connection options such as connectors for radio add ons allow rapid prototyping. FRDM-K64F The platform is equipped with Freescale running the open source boot loader OpenSDAv2 Embedded open source hardware serial debugging adapter. This circuit provides a variety of serial communication, flash programming and operation control debugging options.

II characteristic

·          MK64FN1M0VLL12 MCU (120 MHz ， 1 MB Flash memory, 256 KB RAM , low power consumption, no crystal oscillator USB and one hundred Thin quad flat package with pins (LQFP))

·          Dual purpose USB Interface, with Micro-B USB Connector

·          RGB LED

·          FXOS8700CQ Accelerometers and magnetometers

·          Two user buttons

·          Flexible power supply options - OpenSDAv2 USB 、 Kinetis K64 USB And external power supply

·          Compatible with Arduino ™ R3 Of I/O Connectors are easily accessible MCU input / output

·          Programmable OpenSDAv2 Debugging circuit, support CMSIS-DAP The interface software provides the following functions:

                Mass storage device (MSD) Flash programming interface
                CMSIS-DAP The debugging interface can be realized through the drive free USB HID Connection provides operation control debugging function, compatible IDE tool
                   Virtual serial port
                Open Source CMSIS-DAP software project

·          Ethernet

·          SDHC

·          Additional RF module: nRF24L01+ Nordic 2.4GHz radio

·          additional Bluetooth modular: JY-MCU BT Circuit board V1.05 BT

·          Software support and application development are provided by Kinetis Software Development Suite (SDK) Yes. This is a comprehensive suite, including stable and reliable peripheral drivers, protocol stacks and middleware ( Alternate Sample Code Package / Example ) 。

        For details, please see this picture. There are two USB ports. On the right is OPENSDA. The download program mainly depends on it. There is nothing to say about the reset button. The 5V jumper cap is the power supply mode in the main mode. Then there are various IOs. The small chip in the lower right corner is the accelerometer and magnetometer. The eight holes leaked out are the interfaces of the 2.4G module, and the four holes below are the Bluetooth interfaces, SD、 Buttons are very different from RGB. Such a set of on-board resources is very rich. It is indeed a high-end product of Freescale.

III debugging

    （1） At the beginning, an icon like this will be displayed after you get the development board and plug it in   This is the K64F Flash. In this way, we can't download and debug.
(2) We need to let the development board enter the Bootloader mode

Method: Press and hold the Reset button of the development board, and then use the USB cable to connect the OPENSDA interface of the development board to the computer. When the drive named BOOTLOADER appears, release the Reset key. Its free space is 128KB.

(3) Install mbed program

Download the FRDM-K64F_QSP.zip package（ ）After decompression, copy the k20dx128_k64f_if_mbed.bin file in the FRDM-K64F-QSP OpenSDAv2 Applications directory to the BOOTLOADER disk. Disconnect the development board from the PC and power on the development board again. At this time, the development board is recognized by the PC as a "MBED" drive.

(4) Install the driver for the development board

We download mbedWinSerial_16466.exe（ ）, connect the development board and PC, and then double-click the file mbedWinSerial_16466.exe.

(5) Set the project under MDK

First, you need to install MDK, and then click

Click this button to find the K60 column to download

After the download is successful, we can start a new project and write code. After writing, we need to configure the project.

Under Options ->Debug, select Use as CMSIS-DAP Debugger, and then click Settings to set.

Select SW for Port, Under Reset for Connect, HW RESET for Reset.

4、 Experiments

Because the system is designed and used FRDM-K64F is used as the core control, so it is connected with some external circuits, such as infrared touch keys, 24C16 chips, etc. It is also planned to use nRF24L01+ Nordic 2.4GHz Radio module.

Later, it is planned to use CMSIS library to operate some DSP functions. Some functions are being debugged, and we are particularly grateful to Lei Feng.com for providing a good opportunity for product research and development, so that product research and development is going on smoothly.