Tag: Computer

gnupg: What should I do next in my GPG key after my computer is confiscated by the authority?

Unfortunately, although my passwords are password protected, I fear it is not secure enough. I assume that I lost control of all my private keys now. I still have a backup copy of my private keys, what I want to know is, for my privacy, if I generate a new subkey from my old master key and revoke the other old subkeys, or I must generate a completely new key, sign my new key with the old key and then revoke the old key? Also, my old key is in the "strong set" of WoT. If I generate a new password, does that mean I need to build a trust network from the beginning?

Developing computer software [on hold]

How are great programs like Eclipse made? What course will I be asked to take if I also want to develop huge software? For me, even doing simple programs becomes very complicated. That I have to do?

kernel os – How can the initial "boot" state of a computer be different at different times?

In my experience, sometimes a computer starts normally, and in a period of days, the computer does not start, again, it will start normally again. I'm not a computer expert, so I guess if a computer normally starts up once and then it doesn't, must be due to any change made to the computer between those time points.

My question is motivated to understand the process of starting a computer at a basic level to know how to debug such behavior.

For a specific example, I obtained a new computer with Ubuntu 18.10 that presented this behavior, all the time without internet access, so it is not possible to make updates.

Can you change something on a computer without the user modifying something, also without having an Internet connection?

computer networks – How do web browsers find the MAC address?

While reading my textbook, I discovered that if you want to access a particular web page, your browser will discover the IP address of the web server that hosts the web page and try to connect to it. Then you will transfer a copy of the website to your computer so you can see it.

However, my concern is … I have discovered that the IP address allows sending data to the local area network of the device, but for the data to be sent to the device itself, the MAC address is needed to transfer data from the network. local area to the device.

BUT, in my textbook, nowhere does it say how the computer's web browser discovers the MAC address of the web server. It says that the computer discovers the IP address of the web server through the Domain Name System (DNS).

So how does the computer discover the MAC address of the server?

The answers would be much appreciated.

computer architecture – Cache mapping calculation

A cache has the following specifications:
Block size = 16 bytes
Set size = 2-way associative set
Number of games = 128
Physical address = 23 bits, addressable byte

My questions are:
1] How many blocks principal memory contains?
2] What is the additional memory required for the cache?

Please help. Thanks in advance.

coincidence: I bought a new computer and I would like to transfer data. Windows 10 to Windows 10. Can I use an old 2.0 transfer cable or do I need a 3.0 cable?

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macintosh: How can I update the firmware of my Godox device on a Mac (OSX) or Linux computer?

OSX only options

G3 / F3

Godox / Flashpoint has released an OSX version of the G3 / F3 updater. However, at this time, it only supports updates for the following devices:

  • V1
  • for Pentax TT350-P and Xpro-P
  • AD400 Pro
  • Flashpoint R2 Pro II

For all other devices, or from Linux, however, there are some different ways to do it, if you don't want, for example, to buy a cheap Windows tablet or transport that old Windows XP box that you thought you had removed from storage.

Training ground

If you are on OSX, you can install Windows on a Bootcamp partition and run the G1 / G2 or F1 / F2 applications from there. This has the disadvantages of continuing to use Windows and require space for a complete installation, but it will have the advantages of speed and there will be no problems with USB hardware recognition.

OSX and Linux options

dfu-util

If your device is AD200 or later, and you have an update file .dfu (Device Firmware Update) that requires the Godox G2 updater, you can use the open source dfu-util on the command line to copy the .dfu file to the device, as described by burning1rr in reddit. The basic steps, according to that reddit post, after installing dfu-util are:

  1. Connect the device with the appropriate USB cable and run:
    dfu-util -l.
  2. Verify the value of alt= flag on the way out.
  3. run dfu-util --alt --download where high_value is the value that was printed in step 1 and dfu_filename is the path / name of the firmware update file.

dfu-util, however, cannot be used for updates that require the Godox G1 or the application, since those firmware updates are not compatible with DFU. It is also unknown if G3 updates are compatible with DFU, as Godox publishes them as .bin files.

Virtual machines

If you do not want to mess with Bootcamp or are in a Linux box, it is known that a virtual machine works for Godox and Yongnuo firmware updates. You can find a complete video tutorial here on YouTube.

If you feel stingy and want to try to do it for free, you can use the open source VirtualBox and the free 90-day Windows developer virtual machines from the Microsoft website. It should also work with Parallels or VMWare.

computer networks – How to access LAN (Ethernet cable)?

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Stages of creating a computer game in Unity

I am writing a computer game, but I don't know what is missing, because I collect information on YouTube about unfinished courses by the authors. What stages of development did I learn from the videos:

  • Prototyping (choice of genre, setting, characters, mechanics, concept art, locations of primitives, etc.)
  • The creation of the game (here my knowledge is incomplete)
  • Tests (detect errors, verify the functionality of all functions, etc.))
  • Release with subsequent maintenance

As I understand this process (writing game):

  • Create 3D models (based on concept art, prototypes of locations from primitives)
  • If the model is a character, create an animation.
  • Import models to Unity
  • Customize materials for Unity models
  • We organize prefabricated models (prefabricated) on stage.
  • We write scripts for the interaction between objects.
  • Write a system in the player's inventory.
  • Write a system to save the game.
  • Large knowledge gap (what else needs to be done?)
  • Create the main menu.
  • Collect the project file ".exe".

Complement my list or write your own.

Computer architecture: AMAT using the local failure rate, the global failure rate, the local success rate, the success rate

Consider the following scenario as shown in the image:

enter the description of the image here

I have summarized the previous memory design in terms of failure rates and success rates:

.---.----------------.------------.------------.------------.--------.
|   |                |     0      |     1      |     2      |   3    |
:---+----------------+------------+------------+------------+--------:
|   |                | LMR        | GMR        | LHR        | GHR    |
:---+----------------+------------+------------+------------+--------:
| 0 | L1 cache       | 10/100     | 10/100     | 90/100     | 90/100 |
:---+----------------+------------+------------+------------+--------:
| 1 | L2 cache       | 3/10       | 3/100      | 7/10       | 7/100  |
:---+----------------+------------+------------+------------+--------:
| 2 | Main Memory    | 0/3        | 0/100      | 3/3        | 3/100  |
:---+----------------+------------+------------+------------+--------:
| 3 | Sum of columns | Not useful | Not useful | Not useful | 1      |
'---'----------------'------------'------------'------------'--------'

Here LMR – local failure rate, GMR – global failure rate, LHR – local success rate, GHR – global success rate.
From the table above I deduced the following ideas:

  1. The sum of the global success rates (GHR) of all caches and the main memory is 1.
  2. The formula for AMAT (Average memory access time) can be interpreted as follows:

AMAT = tone + monettwo +
meteronemetertwot3

(or)

AMAT = tone + Monettwo +
METERtwot3

.
where Mone,metertwo are local failure rates for Level 1 and Level 2 caches respectively. METERone,METERtwo are the global failure rates of Level 1 and Level 2 caches respectively. tonettwot3 are access times for level 1 cache, level 2 cache and main memory.
For the example given,

AMAT = tone + 10 / 100ttwo + 3 / 100t3

  1. From point 2 you can say that

METERone = mone; METERtwo = mone*metertwo; and so

  1. The local hit rate of the main memory (or final level cache) is always 1. Here it is assumed that the required word is surely found in the main memory (or final level cache).

Now my question is "Are these points correct?" I did not find any relevant information for the previous points. Are there also more ideas I can get from the table? As a relationship between GHR and lmr, lhr.