My wife sent me an EleksMill as my birthday gift (Thank you! my love). It’s simple but proper designed desktop CNC. However, the document of the CNC machine is as simple as the design. It cost me around 4 hours to assemble the machine from a piece by piece.
After completed the assembling, I found the board was not initialised. So, I downloaded the firmware from EleksMill website. Unfortunately, the official package only supplied the windows application to upload the firmware. For Linux, such as my OS Ubuntu, I have to find out another way to upload the program.
Since EleksMill is based on Grbl, so it can use Arduino tool-chain to upload firmware.
$ arduino/hardware/tools/avr/bin/./avrdude -C arduino/hardware/tools/avr/etc/avrdude.conf -v -patmega328p -Uflash:w:/home/mikespook/Downloads/EleksROM\ V3.8/firmware/mana.hex:i -carduino -b 57600 -P /dev/ttyUSB0
`avrdude` command can be found in Arduino IDE folder `arduino/hardware/tools/avr/bin/` and the `avrdude.conf` file is in the sub-folder `arduino/hardware/tools/avr/etc/avrdude.conf`.
Since November last year, after 2degrees upgraded their network and was starting to abandon 2G cross the region, the 3G connection disconnected every 15 minutes. I know it because we have over 50 movie kiosks which originally were using 2degrees 3G network to sync the data.
We had to move on. Lucky, Spark gave us a good deal to switch the network to them. However, they don’t have the devices we need to connect to the 3G network. After several testing, ZTE MF190 is recognised as the best 3G dongle to be used.Continue reading Make ZTE MF831 works with TP-Link TL-MR3020
Err:8 http://security.ubuntu.com/ubuntu zesty-security Release 404 Not Found [IP: 184.108.40.206 80] Err:10 http://archive.ubuntu.com/ubuntu zesty Release 404 Not Found [IP: 220.127.116.11 80] Err:12 http://archive.ubuntu.com/ubuntu zesty-updates Release 404 Not Found [IP: 18.104.22.168 80] Reading package lists... Done E: The repository 'http://security.ubuntu.com/ubuntu zesty-security Release' does no longer have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. E: The repository 'http://archive.ubuntu.com/ubuntu zesty Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. E: The repository 'http://archive.ubuntu.com/ubuntu zesty-updates Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.
And none of the other mirrors works to me. All of them has the same issue “no longer have a Release file”. I did some research and found the error message actually has another form “not have a Release file”.
The solution is easy but tricky — Disable all sources of `security.ubuntu.com` and replace `archive.ubuntu.com` to `old-releases.ubuntu.com`.
goRBAC provides a lightweight role-based access control (RBAC) implementation in Golang. Normally, the privilege information (roles, parents, and permissions) are saved in the persistent storage, e.g. Database, Files, or Cloud Storage. This post will briefly discuss the technical details of how to load the goRBAC instance from persistent storage and how to save the instance back. In order to make things simple, I will use the JSON file as the persistent storage.
Continue reading How to persist goRBAC instance
All the websites below have a plenty of books and papers for free reading & downloading.
The National Academies Press, free reading and downloading in PDF, account needed for downloading.
Australian National University Open Research Library, all materials come from ANU, fill a form to request the PDF copy.
The University of Adelaide > Library > eBooks, free reading and downloading in HTML, epub, and Kindle.
Curtin University Library, free reading and downloading in PDF.
University of Queensland, part free.
Project Gutenberg, the greatest one, no more explianation.
The New Zealand Digital Library, free reading online.
Cornell University Library, free downloading in PDF.
Code refactoring is not an easy job, but it has to be done in most of the times. I just completed the lightweight role based access control library: goRBAC’s refactoring. There are some feedbacks and questions about the design and usage. I think it would be better writing something to share some design ideas and practice principles which will make things easier.
The master branch of current goRBAC’s source code is intended to be Version 2. While the previous version has been tagged as Version 1 with the v1.dev branch on Github. And this article will only discuss Version 2 (the master branch).
Sunday, a triangular routing would be a perfect plan. I have to admit that the term is borrowed from the mobile network, but it can be figured out, isn’t it?
Followed the previous post: Walking around Mt Albert – Part 1
Alberton, a farmhouse, was built as the residence of Allan Kerr Taylor, who was a notable New Zealand landowner and businessman. Taylor’s family contributed to Mt Albert region a lot. It’s said that the family gave the land to build St. Luck’s Church and donated the church bell. I was planning to visit the Church today as well, but …
Turn back to the house. The gate in the photo is not the original front gate actually. I’m even not sure that if it existed originally. The tour guide said the gate opened at this side just for the reception. The original gate which should be in front of the fountain does not exist anymore. I will show you the fountain latter.