High Frequency Noise Caused by Moving the Mouse

recently, I have experience very weird problem.
old computer(but it works fine) has make high frequency noise whenever I move the mouse.
I could not stand. and I start to find it.

many post tell about it. "oh! it's grounding problem. check your electricity!"
but, my house has perfect grounding already.

and then, someone tell about it. "oh, it's problem of power options on the mainboard. disable the power saving mode!"
but, it's not works properly.

finally, I thought that it's problem of mouse own self.
so, I had check the mouse options. and figured out it.
the suspect is mouse's "Polling-Rate".

Polling-Rate is the rate of checking mouse pointer location.
if your mouse has high Pollin-Rate, you can get more precise pointing.
but it has very high frequency(over 500hz), and makes unpleasant noise forward to speaker.

(This is logitech mouse G-Hub utility. watch yellow box.)

so I have down Polling-Rate from 1000hz to 125hz and DPI from 1600 to 800.

of course high DPI is not main suspect, but I feel that very high DPI help high frequency noise.

so if you has suffer from high frequency noise from mouse, change the Polling-Rate options or get the mouse that has low Polling-Rate.

Keyboard & Mouse input lag issue

for several years, I have suffred from weird problem.

after very first time boot up(cold booting), keyboard & mouse input was very very slow. it's looks like watching a buffering video. but, other application executions are no problem. and one more strange thing is that rebooting(warm booting) was solved this problem.

so, to solve this problem, I was tried many means. changing the BIOS, re-installing the OS(Windows & Linux) and so on. but, nothing changed.

then, I suspected the keyboard & mouse own problem. but it was also not correct. because other well functioning input devices show same malfunction on my PC.

finally, I tried other way. it was the changing the USB ports. I have used USB 2.0 ports for input devices. because ordinary PC recognize input devices on BIOS only when it connected to USB 2.0 ports. but, after changing from the USB 2.0 ports to the USB 3.0 ports, the problem that sufferd me for several years was gone!

I think this problem is very weird. keyboard & mouse is not require broad data bandwidth and more power consumption. but the USB 2.0 ports was not works properly on input devices.

anyway, if you have same problem, change the input devices connection from the USB 2.0 ports to the USB 3.0 ports.

--------------------------------------------

I would like to update.

several month after suffering, finally I figure out what was the problem.
USB has special option that called 'Hand-off'.
maybe many of you will ask me, so what is that special option?
That's the compatibility mode for USB.
explain more kindly, USB can operate low-speed mode that was defined past time. that was the point.

generally USB 2.0 can support USB 2.0 full-speed and USB 1.0. but, because USB is not recognized proper speed perfectly automatic, sometimes misunderstand speed. therefore we have to define the speed explicity.

so, we have to prevent that USB itself change high-speed to low-speed.

If you have same problem, disable the USB 2.0 'Hand-off' option on Mainboard BIOS.
now, I have good feeling like get new USB hub.

good luck!


P.S. my mainboard model is Gigabyte H77-D3H-MVP (Rev 1.1)

DCP-1510 printer setup on Raspberry Pi (and Airprint)

[Driver installation]

1. attach your printer to Raspberry-Pi

2. update upgrade list and then upgrade system
    Command Example : sudo apt-get update
    Command Example : sudo apt-get upgrade

3. install the git, build-essential, cmake, libcups2-dev, libcupsimage2-dev
    Command Example : sudo apt-get install git build-essential cmake libcups2-dev libcupsimage2-dev

4. get the printer driver source code from git repository
    Command Example : git clone https://github.com/pdewacht/brlaser.git

5. let's compile and install the printer driver source code
    Command Example : cmake .
    Command Example : make
    Command Example : sudo make install



[CUPS Installation]

1. attach your printer to Raspberry-Pi

2. update upgrade list and then upgrade system
    Command Example : sudo apt-get update
    Command Example : sudo apt-get upgrade

3. install CUPS
    Command Example : sudo apt-get install cups

4. allow access to printer for users and admin
    modify this file : sudo nano /etc/cups/cupsd.conf
    (bold letters must be added)

        #Listen 127.0.0.1:631
        Port 631
        ...
        <Location />
        Order Deny,Allow
        Allow all
        </Location>
        ...
        <Location /admin>
        Order Deny,Allow
        Allow all
        </Location>

5. allow access to CUPS web interface
    Command Example : sudo usermod -aG lpadmin pi

6. restart cups service or reboot
    Command Example : sudo systemctl restart cups

7. add your local printer at web interface's administration tab
    Address Example : https://192.168.1.3:631/admin
    if you want to use Airprint, check the "Share This Printer" option.



[Airprint Installation]

1. install avahi-discover
    Command Example : sudo apt-get install avahi-discover

2. check the printer sharing option is on



[reference site]

https://help.ubuntu.com/lts/serverguide/cups.html.en
https://github.com/pdewacht/brlaser
https://blog.vinczejanos.info/2016/08/12/raspberry-pi-2-as-print-server-airprint/



Good luck!

Remote printer setup on Raspberry Pi

If you wanna Raspberry-Pi as printer server, this posting is useful for your planning.

The purpose of this posting is how to make pass-through type remote printer server on Raspberry-Pi.
Even though x86 CUPS was support comprehensive features and driver, but I want to small and low-power-consumption printer server. so I decide to make Raspberry-Pi printer server.

first of all, I have to notice this useful posting.

https://forum.manjaro.org/t/how-to-set-up-a-remote-printer-which-is-attached-to-a-raspberry-pi-or-any-other-arm-computer/57056

Download


I was refer this posting and then verified it is working.
thanks for your effort Photon.



Following this step
====================

1. attach your printer to Raspberry-Pi

2. update upgrade list and then upgrade system
    Command Example : sudo apt-get update
    Command Example : sudo apt-get upgrade

3. install CUPS
    Command Example : sudo apt-get install cups

4. check your printer URI
    Command Example : sudo lpinfo -v
    usb://Brother/DCP-1510%20series?serial=E72065E5N670207

5. add printer using its URI
    Command Example : sudo lpadmin -p DCP-1510 -v usb://Brother/DCP-1510%20series?serial=E72065E5N670207

6. check the printer status
    Command Example : sudo lpstat -p DCP-1510 -l
    printer DCP-1510 disabled since Tue 09 Apr 2019 20:24:39 KST - reason unknown

7. enable the printer
    Command Example : sudo cupsenable DCP-1510

8. check the printer status
    Command Example : sudo lpstat -p DCP-1510 -l
    printer DCP-1510 is idle.  enabled since Tue 09 Apr 2019 20:26:27 KST

9. accept the printer
    Command Example : sudo cupsaccept DCP-1510

10. allow access to printer for users and admin
    modify this file : sudo nano /etc/cups/cupsd.conf
    (bold letters must be added)

        #Listen 127.0.0.1:631
        Port 631
        ...
        <Location />
        Order Deny,Allow
        Allow all
        </Location>
        ...
        <Location /admin>
        Order Deny,Allow
        Allow all
        </Location>

11. restart cups service or reboot
    Command Example : sudo systemctl restart cups



Now you can use the Raspberry-Pi as printer server without Raspberry-Pi specific printer driver.
OSX and Windows detect your printer autometically, but you need to prepare printer driver.
especially, Windows need address like this when you add the printer.

    Address Example : http://192.168.1.17:631/printers/DCP-1510



and if you want to remove configuration, use this command.
    Command Example : sudo lpadmin -x DCP-1510





Have a nice day!

MT9234ZBA Modem Setup

Hello, today I'll talk about MT9234ZBA Modem Setup


Terminal setting
==============
bit rate : 9600
data bit : 8
flow control : none


Commands
=========
ATI        // If your input this command, you can see OK sign.
AT%R1&W0    // Then input this command, setup will be done. and every input will be stopped.

my whitebox systems

If someone who plan to make virtual host machine is, in my think, maybe need reference model.

So, I'm going to show you my whitebox specification.

At first time, I regarded about AMD system, it has enough physical cores and performance.

but changed my mind. because there was no latest reference anywhere. it was big risk for me.

As you know, intel i7 series processor is recognized as Xeon E3 series processor in vSphere host machine. It's point why I should configure this systems.



System 1 (Host1)

Intel ivy-bridge i7-3770   
Samsung DDR3 8G PC3-12800    4ea
GIGABYTE GA-H77-D3H rev.1.0 (built in Atheros AR8151 NIC)
WD 1TB BLUE WD10EZEX    1ea
500W Power supply
Realtek 8168E    3ea
Realtek 8169    1ea
Intel Pro/1000 PT Dual port    1ea


System 2 (Host2)

Intel ivy-bridge i7-3770
Samsung DDR3 8G PC3-12800    4ea
GIGABYTE GA-H77-D3H rev.1.1 (built in Atheros AR8161 NIC)
WD 1TB BLUE WD10EZEX    1ea
500W Power supply
Realtek 8168E    3ea
Realtek 8169    1ea   
Intel Pro/1000 PT Dual port    1ea


System 3 (iSCSI Storage and vCenter Server)

Intel ivy-bridge i3-3220
Samsung DDR3 4G PC3-12800    4ea
GIGABYTE GA-H77-DS3H (built in Atheros AR8161 NIC)
Samsung 840 series EVO 500GB MZ-7TE500B    1ea
WD 1TB BLUE WD10EZEX    2ea
500W Power supply
Realtek 8168E    4ea
Realtek 8169    2ea



and recently, vSphere 5.5 was released. at this release, realtek NIC driver is not included.

so you must customize image yourself. of course customized realtek NIC driver(support cummunity level) has compatibility with vSphere 5.1 and 5.5.

Using this machine, I had have test Windows Server, Lync, Ubuntu Server and Cisco virtual machines. It works well so far now and It was good choice.


Good luck.