Hahahaha... Totally agree!!! Comments above or on the same line (if it's a very simple comment)... Edit: And what about useless comments???... Have you ever wrote those???... Like: // Check if a > b if (a > b) { (...) } Hahahaha... It seems too stupid, but I must confess I've done it a couple of times...
modified on Thursday, November 12, 2009 6:49 AM
I don't think they're that expensive as most of people thinks... You may want to visit sparkfun.com and check under the sensors -> ID section (on the left pannel)... You can get an RF-ID Reader Module (like ID-2, ID-12 or ID-20) between 25-35$ and the fancy USB interface for PC for only 25$... The magnet card reader costs 60$ and the reader/writer costs 140$... You don't need a writer for RF-ID tags, they're pre-programmed with an unique ID... These modules (ID-x, the differences are internal/external antenna and range) are very very very extremadely easy to use with microcontrollers!... They only need power supply (Vcc and Ground connections, 5V I believe, I don't remember) and they just "spit" a TTL UART-like (RS232 compatible with an MAX232 chip) stream with the code of the card you just approached to it (they also have some Wiegand and whatever compatibility mode) and the microcontroller might read it using HW or SW UART... It takes about 5 lines of code in a microcontroller (exagerating a little, of course) to do this task... If you are not messing with microcontrollers, you can get the USB interface in which you might plug in one of these modules (I can't give you further details on this because I haven't used it, only the modules)... Anyway, I don't think you'll use a PC to control all the distributed readers in the laundry, will you??? :~ All the detailed info (datasheets, etc) is on the web site mentioned before... Hope this helps!!! Cheers!!!
I've always liked programming. Although I'm an Electronic Enginner, the circuit design area of electronics never called my attention. During my carreer I took classes of digital desing area and programming-oriented assignatures. I was increasing my programming skills, but then there was a breakout during my thesis (I had to write propetary USB device drivers for windows) and to achieve such task, I read: "Writing Windows WDM Device Drivers" by Chris Cant... So far, the best book I've ever read!!! It changed my entire vision about Operating Systems (expanding it and getting it to detail)... And since device driver programming is very strict (you can't just allocate a memory buffer and not test if O/S actually returned a valid pointer, or Blue Screen of Death comes up), I learned a lot of techniques to avoid bugs, memory leaks and working in multi-threaded environments with reentrant routines, etc... So... Great Book!!!... Changed my life, from a programmer's point of view... XD
I agree...!