Tesseract OCR with C++, OpenCV, and wxWidgets

Tesseract is a free optical character recognition software and it is considered one of the most accurate open-source OCR engines [1].

• Installation on Ubuntu
• Using tesseract command
• Tesseract C++ API with OpenCV
• With wxWidgets

Getting Started with FRDM-K64F

To use FRDM-K64F with the latest MCUXpresso IDE, you need to update the firmware for its debugger. It is similar to FRDM-K82F where the details can be seen at the following post.

http://cool-emerald.blogspot.com/2020/01/getting-started-with-frdm-k82f.html

There are only a few minor difference between FRDM-K64F and FRDM-K82F to get started. Therefore, I will only list some major points here.

Figure. FRDM-K64F board

Original OpenSDA appears as MBED drive. And it is not working with MCUXpresso. To update the firmware for its debugger,

• Disable 'Windows storage services' ( https://os.mbed.com/blog/entry/DAPLink-bootloader-update/)
• Hold reset button and connect the device to a USB port. It should now appear as a drive called BOOTLOADER
• Drag and drop bootloader ‘0244_k20dx_bootloader_update_0x5000.bin’ into the drive.
• Remove and reconnect without holding reset. Board shows as ‘MAINTANCE’.
• Drag and drop Segger jLink OpenSDA for board specific firmware for K64F (‘02_OpenSDA_FRDM-K64F.bin’) which is available at https://www.segger.com/downloads/jlink#JLinkOpenSDABoardSpecificFirmwares
• Remove and reconnect without holding reset button. It now appears as ‘FRDM-K64FJ’
• To use JLink , open cmd and enter
  
  

  > cd "C:\Program Files (x86)\SEGGER\JLink"
  > JLink.exe -speed auto -device 'MK64FN1M0xxx12' -if SWD
  

  
  
  
• At the JLink prompt
  
  

  J-Link> r
  J-Link> erase
  J-Link> q
  

  
  
  
• After that, it should be OK to use MCUXpresso

ADS1115 ADC

ADS1115 is a precision, low power, 16 bit 860 SPS I2C analog to digital converter (ADC). It has internal reference, oscillator, and programmable comparator. ADS1115 modules are readily available at online markets like AliExpress and Adafruit

Figure 1. ADS1115 Adafruit module
( learn.adafruit.com/adafruit-4-channel-adc-breakouts/downloads).