Unsigned and signed shift:logical shift and arithmetic shift

In C, we usually use left shift and right shift operation << and >> to operate multiple / divide to variable with power of 2,ex: 4<<2  = 16

But when we use the signed variable and the shift operation we must consider the singed bit.See the below example code.

Since the C language support the arithmetic left shift and logic right shift,  we must consider the signed bit to  avoid some bug in code.



Ref:
     1.Logical Vs. Arithmetic Shift
     2.C语言中的逻辑右移和算术左移

CC2640: Merge app and stack hex file

1. Install Python2.7
2. Open cmd.exe type > pip install intelhex
 

3. Use below instruction to merge your hex file

Ref:
      1.CC26x0 SimpleLink™ Bluetooth® low energy Software Stack 2.2.x Developer's Guide
         section 2.6

GO: Development a simple windows GUI use lxn-walk package(2) -- Combobox and Button

1.Create the project folder and win_gui_v1.go in your go work space
   > cd ..\src\
   > mkdir win_gui_v1
2.Copy the .manifest file and modify to your_execution.exe.manifest
 

3.Code
3.Result

 











Ref:
      1. Go实战--使用golang开发Windows Gui桌面程序(lxn/walk)
      2. ComboBox 類別
      3. lxn/walk/examples

GO: Development a simple windows GUI use lxn-walk package(1) -- Getting start

"Walk is a "Windows Application Library Kit" for the Go Programming Language.
Its primarily useful for Desktop GUI development".  In this series I try to build a simple terminal program to commnunicate via COM port.

1. Getting start
    >   go get github.com/lxn/walk

2. Build the example
     >   cd ..\src\github.com\lxn\walk\examples\imageviewer
     >   go build

3. run the imageviewer.exe

  

    

Ref:

    1.  lxn/walk

GO : List all the serial port in windows use golang-sys package

We can easily get all the serial port in windows using regedit.exe

In our application we read the windows register key `HARDWARE\\DEVICEMAP\\SERIALCOMM` through windows API and list all the sub key and value.

Github project: win_serial_console

Ref:
    1. getting-started-with-golang
    2. golang-sys package
    3. Why does the RegQueryValueEx() function return ERROR_FILE_NOT_FOUND while trying 
    4. 搜尋電腦上所有的 RS232 Ports
    5. Enumerating Registry Values in Go (Golang).
    6. System Error Codes (0-499)

CC2640:Change RF front end mode and bias

1. In ../main.c define your own BLE configuration template.
2.The option and default configuration is define in ../ble_user_config.h
 

The internal bias and external bias is determine by the RX_TX pin, which didn't implement in 7x7 package.In our application we use the CC2592 as PA and use 5x5 package for smaller footprint, and the configuration is differential mode internal bias.


Ref:
      1.CC26xx HW Training : RF Front End options and Antennas
      2.CC2640 在 Beacon 应用中的实现方法
      3.CC26x0 SimpleLink™Bluetooth®low energy Software Stack 2.2.xDeveloper's Guide

CC2640:Use System_printf in project.

1.I use IAR as IDE to develop CC2640 BLE project and XDS100V3 as debugger.First make sure           enable the Semihosted and Via semihosting in General Options.
 

2.Add below code in app_ble.cfg file.
 

3.Add include header file and test.



4.In debug mode enable View->Terminal I/O and we can see the Hello World! in terminal.

Ref:
     1.System_printf and printf() on CC2650 sensorTag
     2.System_printf supported format specifications