Recently I needed to fill up some form for submission, in soft copy. The template file provided was a MS Word document, but for some really stupid reason it was marked read-only. When I tried to edit the document, this helpful sidebar appeared.
When I clicked the “Stop protection” button I was prompted for a password. I didn’t want to waste time trying to recreate this whole form, nor do I wish to hand-write it.
Written by Darell Tan on 26 Jul 2010Share Comments
I reformatted my computer yesterday and installed Windows 7. I installed 2 apps - Winamp and Mp3tag, both of which cannot accept files that have been dropped onto them. Hmmm… that’s strange. It turns out that this is a security feature, part of UAC. Instructions on how to fix it is detailed here. In the Control Panel item “Administrative Tools”, under Local Policy, disable this item called “User Account Control: Only elevate UIaccess applications that are installed in secure locations”.
Written by Darell Tan on 15 Jul 2010Share Comments
Recently I wanted to use a really tiny, low pin-count microcontroller for a project, so I decided to buy a few Atmel ATtiny10 to experiment with.
To get it working, I would need a compiler and a programmer. I like working with Atmel chips because they have cross-platform development tools. The Arduino IDE that I’ve been using comes with avr-gcc and avrdude, both of which are really awesome open source tools for compiling and uploading code to the microcontrollers. If you just want the tools without the Arduino IDE, you can get the WinAVR package.
However both of these tools do not work with the ATtiny10 yet. I do not expect a C compiler, but even the GNU assembler that comes with avr-gcc still doesn’t support this chip. avrdude recently added support for uploading to the ATtiny10, but only through the STK or AVRISP programmer, which I didn’t want to fork out money to buy.
Here’s another reason why I think dedicated kiosks like these should never run Windows. … has Windows-based Fuji photo kiosks in at least some of its stores that don’t run antivirus software, and are therefore spreading infections… via customers’ USB storage devices. The same problem occurs with shared computers in our school’s lab computers - people come in with their thumbdrives and use it to save their files, but at the same time the virus on the drive autoruns.
A few semesters back, our school started trial runs to use these “clickers” as well. At that time I was thinking of cracking it open to see what makes it tick, as well as evil plans like trying to impersonate other clickers or sniffing what other people’s responses were. I only managed to peel back a bit of the plastic in front, but since the clicker was brand-new and I had to return it in a good condition, I didn’t dare to proceed any further than that.
This is an interesting read. I, too, just assumed the ±10% included the whole range and it would be of some random distribution. “Design your circuit to use values that lie 7% away from the nominal standard values, either higher or lower, and you’ll find plenty of those in the bins when you do your hand selection.”
I had these chips extracted from the old motherboards I threw away some time ago, and I thought I’d have some use for them some day.
These are Electrically Erasable and Programmable Read-Only Memory (EEPROM) chips which are used to hold the BIOS code. I was curious to find out what’s in these chips and if I could re-use them for storage in my projects, so I decided to interface with them.
Written by Darell Tan on 17 Jun 2010Share Comments
I have a 4-digit display module and I was thinking of a way to interface it with the microcontroller with the least number of pins. The display came from a kit that I had bought last time, and the kit used CD4511 (BCD to 7-segment decoder) along with an MC14553B (3-digit BCD counter) that has a built-in multiplexer that drives 3 (of the 4) digits. If I go with a similar setup, I’d require 8 pins to interface with a micrcontroller, 4 for BCD to the CD4511 and 1 for each digit for 4 digits.
I own a BenQ DW1640 DVD drive and like many other people, the drive tray will no longer eject and retract properly. Following advice from a blog, I took apart my drive and indeed the tray mechanism is driven by a rubber belt. Although it seems to run properly by manually spinning it, it still doesn’t work after I’ve oiled some gears. I have no rubber band of such a small size lying around, so I either have to go out and buy another rubber belt to fix the drive for the next few months (maybe years), or I can go out to get a new drive that doesn’t use rubber belts.
