Wednesday, July 19, 2017

TAB key autocomplete not working in xfce4 (no file completion)


First I noticed that bash autocomplete (also known as "shell file completion") stopped working. Pressing TAB I only see the cursor to flash a little and got no filename or command expansion.

All relevant lines in .bashrc were in place and correct.

Then I noticed the TAB key was not working in any application (e.g. text editors, mail, ....): TAB was doing nothing. So it is obvious that autocomplete couldn't work as well.
So I assumed that by pressing the TAB the applications receive a wrong code. As a counter-proof I've found that directly typing the TAB code (Ctrl-I) solves the problem. Remote ssh sessions worked fine.
Started to suspect an xfce4 wrong setting...

I've found the following solution:

Monday, December 28, 2015

How to test the TDK TBD420NR CCFL inverter

TDK TBD420NR inverter with some signal paths highlighted.
TDK TBD420NR inverter with some signal paths highlighted.

The TDK TBD420NR CCFL inverter is found in many laptop screens. I've found it in an HP Pavillon DV9500.

LCD screens with CCFL backlight are prone to failures and  you are often in doubt if it is an inverter or CCFL lamps failure.
So it is very useful to have a way to live check the inverter before ordering a new one just to discover that the failure is elsewhere.
I've found a way to live check the TDK TBD420NR.

Sunday, December 14, 2014

Installing an HP OEM Windows 2012 R2 Essential server as KVM Guest


I have an HP Proliant DL385p Gen8 box together with a HP/OEM installation disk of Windows Server 2012 R2 Essential.
On the iron I've installed Ubuntu Server 12.04.5 64bit plus xfce 4.1 (horrible: avoid it!) and KVM latest version available in ubuntu repository at the time of this writing (Dec2014).
The windows server is going to run as a guest over KVM. I have plenty of configurations like this perfectly working where, however, the Windows software is not OEM..
Here, a little while after the windows server installation CD boots up in the guest, it stops with the following message:"This system is not a supported platform": the hardware platform must be an HP and the actual one is not. No way.

Monday, March 3, 2014

ARDUINO UNO as a USB to GPIB controller - version 6.1


TEK2232 loves Arduino
TEK2232 loves Arduino
Fluke PM2534 loves Arduino
Fluke PM2534 loves Arduino

Disclaimer:
This program is provided as is. It is a hobby work.
It doesn't work correctly. It has not been tested. It can damage your Arduino and the device you connect it to.
Can have unexpected behaviors, can get stuck at any moment, can read and write data to/from the device in ways you might not expect. It can send wrong or erratic commands to the device. Can display data that differ from the actual data the device sent out. Can address GPIB devices
differently from what you might expect.
I have not conducted any speed test; the maximum speed supported is simply unknown.
Is does not follow any official standard. Only a minimum set of the functions included in IEEE-488 is barely emulated.
Hardware limitations: the lack of a GPIB line driver has two major implications: first: your Arduino is directly connected to the device GPIB port without any form of electrical protection of buffering - this can potentially damage your Arduino and/or your device; second: what can happen if you connect more than one GPIB device to the BUS is unpredictable both from an hardware and software point of view. I only experimented with a single GPIB device connected to the BUS.

Creative Commons License
Arduino USB to GPIB firmware by E. Girlando is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Permissions beyond the scope of this license may be available at mailto:emanuele_girlando@yahoo.com.

After nights spent coding, this post is about version 6.1 of my USB to GPIB controller software for ARDUINO UNO.
Version 6.1 ??!! Yes, that's it! This is actually version 2 of my software, but because some third party software - actually KE5FX GPIB toolkit -  relies on the content of the output string as issued by the "++ver" command to work properly, I had to force the string "version 6." as part of the" ++ ver" command output. So .. this version has become version 6.1. 

Version 1.0 has been presented in this related post.
Version 1.0 was very crude. Most a beta version to verify the feasibility of this project.
I want to thank you very much all of you that provided me feedbacks.

Wednesday, February 5, 2014

Arduino UNO as a USB to GPIB adapter / controller


NOTE:
This version is OBSOLETE!! Please go to this post for the 6.1 release software and documentation.
---

Version 1 of this project is aimed to provide a cheap and quick GPIB solution to those that need to gain control over a single instrument and interact with it (e.g. to calibrate instruments that can be calibrated by GPIB only -- 6632A Power Supply being a good example).

I supposed that cheap adapters were available on the market to interface GPIB instruments with a PC. I was wrong. The only feasible solution is to go with a Prologix USB to GPIB converter, still it would have cost me some tens of bucks.
Other solutions required buying or building hardware.

On the other end I had an Arduino UNO floating around on my bench waiting for a problem to solve other than blinking leds or writing "hello world" on an LCD..

So I decided to face the challenge of writing down a c++ program and have the Arduino play the adapter role I was looking for.
To make a long story short.. (I supposed that GPIB was simple at least as much RS-232 is, .. and it is not! I was wrong again!) after reading a lot of IEEE-488 documentation and giving a try to a similar program I found over the internet, I got a decent implementation of a GPIB controller out of my Arduino UNO. This post is dedicated to describe the project.