Author: admin

Nand / Nor

i know any gate can convert to NAND or NOR, asked many time why people always use NAND instead of NOR, no one can answer, but i found the answer now. NAND need voltage, NOR need current.

2023/07/19 0

香港搞open source搞唔起的原因

香港永遠唔會出到外國咁成功同大型的open source project, 原因如下: 原因一: 香港無錢 香港人最驚被人話無錢, 但係開源呢單野上正正就係無錢, 可以話係窮到一蚊都無嗰種. 唔信你可以申請下創新科技署同科學園, 你話你搞open source睇下批唔批到條毛俾你. 原因二: 香港人無堅持力同投入度 你可能會反駁香港人都搞好多open source project, 但係得罪講句啲project係停留係小工具嘅層面(我唔係串, 我只係講事實), 係級數同規模上無得同外國比. 至於點解呢世做小工具, 原因不外乎香港人堅持同投入度都極度低下, 無人可以做一單野用十年做單位. 原因三: 香港人好鐘意得個噏字 香港真係太多阿叔, 可以睇 創科阿叔心理分析 原因四: 香港人啲技術低 HK developer = App developer, 個底係打工仔一名, 啲咩科學改變世界唔會關佢地事, 佢地只關心轉工. 原因五: 香港學界無力 香港嘅學界基本上一蚊都揾唔到sponsor, 如果你揾啲教授合作, 佢地唔係自己着數哂就唔會做, 一係就係咁得個吹字. 講技術, 香港學界有幾多料大家都知, 出論文可能得, 但要開發啲實際野唔洗諗. 原因六: 香港無一群有科學使命嘅老細 所有老細為賺錢, 佢地可能都係讀科學出身, 但個底唔係科學人, 可以話一啲科學精神都無. 佢地搞野要三個月後攞出去賣,…
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2023/07/18 0

Heltec Arduino super simple tutorial

Buy from here. Offical website. Steps to make it work in arduino: 3. Burn these examples To try the wifi example 2. Change the wifi ID and password, case sensitive 3. Run it and see the result in serial monitor, set the baudrate to 115200. It grab the html from outside, see the code then…
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2023/07/17 0

Arduino Nano V3.0 + NRF24L01

This little board is nearly the same size as nano but embedded with a NRF24L01, and also very cheap $4 USD. To make it works: The “RF24 > Scanner” will works like below 100% compatible with Arduino nano

2023/07/17 0

CLB and IOB design

altera and xilinx probably copying each other

2023/07/16 0

Remote riscv-qemu gdb in vscode

3. Change the no of hart to 1 Result : Step over fully work

2023/07/15 0

HVPP reset Arduino Nano fuses

2023/07/14 0

Programming Arduino using STK500 ISP

STK500 is better than MKII since it supports high voltage programming, it can reset fuses from any status. Step 1: Install the driver. Must be version from date 7th Oct Plug in the USB, if it detected wrong driver, update it by select specific folder’. Need reboot the computer to take effect. Step 2: connect…
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2023/07/12 0

Programming Arduino using MKII ISP

I got MKII ISP from here. To program Arduino Nano via Microchip studio, nothing special, remember have to select the chip. And Nano D8 pin is B0. Nano bootloader can be found in here.

2023/07/12 0

STM32 power up

Did it one more time and

2023/07/07 0

Step to make icesugar 40 works

Simplest steps To make the RGB led work, put on these three jumpers

2023/07/05 0

solder resistors to make oled change from spi to i2c

Arduino To make it work in Arduino, don’t use adafruit SSD1306, you have to use SSH110X library. Run the example, no need to modify anycode.

2023/06/27 0

STM32 + OLED 0.96 4pins I2C, works

This video works , sample code is in here.

2023/06/21 0

Arduino Nano IIS + Oled

this youtube works. Oled 0.91 and 0.96 inch both work. Oled can buy in here. The adafruit example is 128×32, need to change to 128×64 for 0.96 inch oled. One thing becareful, 0.96 oled 128×64, the address is still 0x3c, not 0x3d In Arduino IDE, change the address to “3C”, otherwise won’t work

2023/06/17 0

We teach kids for free

Kids coding training, lions clubs

2023/06/11 0

Teaching teenagers to understand logic

Teaching always sharpen my knowledge, fill up all the missing gap of my skill

2023/06/07 0

Powerup STM32 by breadboard

I found something:

2023/06/07 0

ATMega 328p use ext 16M oscilator

2023/05/25 0

Very good arduino uno clone

bought from here

2023/05/08 0

Step to run icesugar-nano

Bought from here. user manual:  7 serial driver: and semantics: Follow . If you got this error: fatal error: ‘ftdi.h’ file not found, then modify in /Users/peter/workspace/icestorm: Edit /Users/peter/workspace/icestorm/iceprog/Makefile All examples in , just drag the demo program from demo folder or build it…
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2023/05/01 0

Arduino check I2C addresses

This code can check I2C address from multiple devices

2023/04/27 0

Arduino controls two 1602 LCD

One LCD need to set the jump at back to have another I2C address

2023/04/27 0

ESP32 on arduino, simplest tutorial

Got this board from Taobao. Follow schematic:  Code:pxc4doc:  Code:NICE  or download here If you failed to run the code for this. Hold “Boot” button while uploading the code If you meet “the port doesn’t exist”, do:

2023/04/27 0

STM32 – 自古成功在嘗試


2023/04/21 0

STM32 controls 4 digits 8 segment led

MyFunction.c Control Code

2023/04/20 0

01.54 OLED with STM32 example

Buy from here. Example is in here

2023/04/18 0

Create a dummy driver for openocd

We are developing our own risc-v so we need to have to ability to modify openocd. Here is the quickest guide for you to start when you type “set $s1=0xaabb”, it will jump to here

2023/04/12 0

Very small STM32 board

Buy from here , model is STM32F103C8T6

2023/04/11 0

Basic tutorial for blinking led for STM32F411

Tutorial: Create the project Step 1: Open STM32IDE, create the project, choose the right MCU Step 2: Type in project name Step 3: This is project structure Step 4: LED is assign to PC13, set it to GPIO output Then it will generate the setup code Step 5: Blink the led in main, there is…
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2023/04/08 0

PNP create a new list get 403 access denied

Create a new list in SPO via PNPjs will get 403 access denied, run this script to solve it

2023/03/20 0

Load jar and dynamically create object from it

Two maven project, project A load the project B jar, create the object dynamically and invoke the method Project A: Project A: Project B:

2023/03/17 0

Photo – 2022

2023/03/10 0

SEMU call graph

This graph generated by graphviz, helping students easier understand Professor Jim Huang’s SEMU RISC-V emulator

2023/02/27 0


啲人問點解香港SI界唔係好似歐美咁,代理隻product跟著自己改裝,跟住越改越advance,咁就要由SI界嘅本質講起 香港SI嘅本質就係做trade 香港係轉口港,香港嘅SI本質無異,兩個字講哂就係做trade,姐係做買賣,左手入貨右手出貨。用一個好啲嘅比喻,SI就好似百老匯,入左啲冷氣你要咪送去你屋企裝囉。唔同嘅只係做嘅客係公司客,賣嘅貨係專業啲咁解。做trade無問題,賺到錢嘅生意就係好生意,香港做得大嘅IT公司基本上都係做trade。如果認清左個本質,咁你就會解釋到呢幾件事

2023/02/13 0


講得好step by step

2023/02/10 0

QEMU PLIC call map

After hacking the qemu risc-v source code, here is the PLIC call map

2023/02/06 0