[RPi] config setting tool

• use RPi config tool

$sudo raspi-config

[Programming] void(p);

• 今天 diff 兩個實作的程式碼, 某 function 的差異是多了一行

  void(p); 

  其中  p 是 function 參數
• 這執行上完全沒有效果, 主要作用是避開有些 compiler 會有變數 unused 的 warning, 而 compiler 把 warning 也直接以 error 報錯時, 會 build error, 那可以用這方法避開.

[RPi] GPIO

Tutorial

tutorial slide

tutorial git 

homework

GPIO.setmode

register events callback

GPIO.add_event_detect(GPIO_num, event, callback, time)

 

[OpenCV G-API] Graph API

• What?
• Architecture
• Sample
• Reference
• OpenCV official: Why Graph API?

[OpenVX] portal

• What is OpenVX?
• OpenVX (Open Computer Vision Acceleration API) is a low-level programming framework domain to access computer vision hardware acceleration with both functional and performance portability
• Spec.
• NN solution
• Sample
• Sample application
• sample implementation (for vendors)
• Reference Guide 

[OpenCL] Portal

• Concept
• Architecture
• Host
• Device (run Kernel)
• 
  
  
• Sample
• Reference Guide

[RPi] GPIO pin

GPIO.setmode時搭配使用

• GPIO.setmode(GPIO.BOARD)

  : 主要參考 pin#, Z字形編號

• GPIO.setmode(GPIO.BCM)

  : 採 GPIO編號, e.g. GPPIO7

[SW] Feature development framework

• Requirements (SRS) / Motivation
• source (where)
• internal
• external
• policy: inside-out, outside-in
• non-feature requirements
• performance
• cpu usage, memory bandwidth, size, latency
• preemption overhead
• init, peak (when)
• security
• Design (HLD)
• architecture design, cooperation model (protocol stack/SW stack)
• HW/SW/ feature team / Project team
• comparison with competitors
• Maintenance
• issue distribution / human resource estimation
• Case study

     

[RPi] Connection

• Raspberry Pi (RPi) 連網路
• Ethernet, 直接連接網路線到區網
• WLAN, 需設定 AP (Access Point) 的 SSID/password
• 可以編輯 /etc/wpa_supplicant/wpa_supplicant.conf  (Ethernet 連接後編輯, 或在 /boot partition下編輯)

  network={
      ssid="YOUR WIFI NETWORK NAME"
      psk="YOUR WIFI PASSWORD"
  }
  

• 或可透過像 BIOS設定的 raspi-config 做設定

  sudo raspi-config 

• 連接 RPi
• Find RPi in LAN

  arp -na | grep -i b8:27:eb
  

• Connect RPi (assume IP is found by previous script)

  ssh 192.168.1.111 -l pi
  

• Connect RPi with GUI

  ssh -X 192.168.1.111 -l pi

• Note: MaxOSX Lion 之後預設不支援 X11, 須自行安裝 Xquartz 
• Copy files (scp)
• // file tmp.txt on RPi home directory (192.168.1.111)

 scp pi@192.168.1.111:tmp.txt ./ 

• Reference
• 如何在沒有螢幕或鍵盤的情況下設置Raspberry Pi

[Python] 執行 executable binary

• 透過 os package, 可以設定 environment variable 與執行的 binary
• Sample: wrapper_call_executable

import sys
import os

lib_path = sys.argv[1]
exe_path = sys.argv[2]
bin_parameters = sys.argv[3]

os.environ['LD_LIBRARY_PATH'] = lib_path
os.system(exe_path + " " + bin_parameters)