As one of the goodies launched during current WWDC 2013, Apple has released a developer preview of Xcode 5 and detailed some of the new features it offers such as Automatic Configuration, Test Navigator, Bots, Auto Layout, Asset Management, Debug Gauges, Source Control, and more. Looking over some of the videos of the WWDC Sessions Videos, […]
Writing serial drivers for OS X (1)
At least one thing can be improved on Mac Dev Center: the code sample repository. I am not talking about documentation. In this particular case, there’s not much new to write about. The I/O Kit documentation (grab the pdf while it is stil there) is sufficient. On the shelves are tons on books about C and […]
Rigol Spectrum Analyzer !
I’ve kept drooling for this for several years. Today I finally got it ! Moreover, it seems it is fully-option enabled, which is kinda weird because I haven’t ordered for such. However, here it is: the Rigol DSA 815 TG Spectrum Analyzer with tracking generator. This will enhance my lab’s capabilities in RF electronics and […]
C#, SCPI and Keysight (Agilent) DSO-X 2002A
This post is a relic. The initial draft dates back in January 19, 2013. And was left as draft ever since. Past couple of days I was busy — among other things — learning a new programming language, C#. 🙂 Ok, here’s the deal: my scope (KeysightAgilent DSO-X 2002A) is SCPI–compliant device. If you remember, the reason behind […]
__attribute__((packed))
The keyword __attribute__ allows you to specify special attributes of struct and union types when you define such types. This is mostly encountered when designing code with particular care on memory footprint optimisation. I have encountered this several times in some Apple headers while digging for documentation for my kext projects, and I thought it […]
LTSpice Parameter Sweep
While designing/ working on my APRS project, I used LTSpice IV for some simulations. For those that don’t know, LTspice IV is a high performance SPICE simulator, schematic capture and waveform viewer from Linear Technology. It is a freeware and can be downloaded from this link. Versions for my both platforms exist, Win 7.0 and Mac. […]
144.8 Mhz TX for APRS (3)
This is a quick update post. The road I took with this little project is slowly getting to a dead end due to what it seems to be a lack of available crystals for 144.8 (like 48.26 or 28.96 MHz, for using the third or fifth harmonic). I believe that, currently, all APRS modules are […]
Simple stuff: viewDidLoad vs. viewWillAppear
I was coding today for a small project I have. A very simple iOS application that has a very simple storyboard, two different paradigms for iPhone and iPad, but very, very simple. While coding I was struck by the fact — frequently forgotten — that we tend to ignore the obvious. Ok, here’s the deal: take one […]
144.8 Mhz TX for APRS (2)
More work today and yesterday on this project. Still locking on 144 MHz, but this is normal, the crystal I used is a 48 MHz overtoned, working on the third harmonic in this case, thus spot on 144.0 MHz: I managed to clean the output, at the expense of transmitted power. I used a 7-pole 2m bandpass […]
144.8 Mhz TX for APRS
Been busy at work lately, but still had some time for myself. Latest idea: a low-cost APRS beacon, done with a classical 144.8 Mhz TX and a μController. AX.25 on air. Automatically. So these days I’ve been busy making this: Winding coils, soldering, measuring. Fun. The frequency is remarkable stable, given the rudimentary nature of this. For example, […]
“Auto Layout on iOS Versions prior to 6.0”
A short reminder, because I ran into this today and Xcode’s very poor at providing you useful verbosity when debugging Auto-Layout stuff done in Interface Builder. Sometimes (Xcode 4.x and 5.x) you might get the following errors when building an iOS project: Going to each error does not help much. Debugging IB auto-layout errors is […]
The Indestructible LDMOS
Mailbag today 2 ! This time from NXP. OMFG, look what I got ! This baby will definitely end up in a power RF amplifier for my Ham Radio fun time. This will be a project. THANK YOU NXP ! Got them both today ! And I have to tell you, the girls and guys […]
IOUserClient and IOExternalMethod
While developing the OS X driver for my Agilent DSO-X 2002A oscilloscope, I ran into a topic that I found to be poorly documented. It is about interaction with a device driver. There are several ways to communicate with a device driver from client space (the application). One is by modifying driver properties. This method requires […]
Agilent DSO-X 2002A driver for Mac OS X
December again, another year passed. Traditionally, this is a month when I am taking a long break. But I was up to something in the past days and I wanted to share. I have created a driver for my KeysightAgilent DSO-X 2002A oscilloscope. Maybe not a big deal, but huge for me because this is […]
Writing a (working) USB driver for OS X
For some time I was struggling with an ambitious project, to write a Mac driver for my Agilent DSO-X 2002A oscilloscope (see here). The reason behind this is SCPI and the opportunity to reach fresh perspectives in computer–measurement instruments’ integration. However, it was not an easy way. More of a reverse–engineering project, was very time–consuming […]
FTDI Chip Utilities
I was struggling for some time to make my Mac communicate via bulk endpoints with an Arduino. It is part of a larger project of an USB-controlled Lab PSU that I am currently in prototype stage. Part of these problems solved when I finally realized that you cannot use Arduino serial ports to mimic USB […]
Low Power Digitally-controlled Dual PSU
It comes a moment for any electronics hobbyist to build a power supply unit. Probably is one of the most useful and basic projects that you can go for. Well… one can easily buy those, but what’s the fun then ? However, the majority of PSUs available on the market are high-power (high-current) PSUs. With […]
Missing WordPress Link Manager
WordPress users that updated the blog platform to version 3.5 might have observed that the link manager is missing from the admin pages: It seems that WordPress announced this as one of the major core changes when they released version 3.5: One other major change is the Link Manager. If you’re using it, you’ll want […]
Changing FTDI descriptors
I was struggling for some time to make my Mac communicate by USB with Arduino. It is part of a larger project of an USB-controlled Lab PSU that I am currently in prototype stage. Part of these problems solved when I finally realized that you cannot use an Arduino as an USB controller simply because […]
Using arrays of checkboxes to store and retrieve WordPress options
I am into a complex task: for some time I’ve wanted to update the theme of this site and make it more versatile. Despite my obvious lack of time, the content is increasing steadily, so is the number of visitors, and I feel more and more often the need to structure better all these posts […]
UIPickerView Tutorial — part 2
Before we continue the second installment in the series of basic tutorials about UIPickerView usage and customization, a short digression. Most Cocoa/ Cocoa Touch tutorials assume that all connections to delegates, data sources and outlets are done visually in XCode. Our previous example was no exception. You can see from the project (gave the link below) […]
Bootable USB Drive with OS X Mavericks — Fastest Way
Apple released its latest OS X version, 10.9 or “Mavericks”. Quote Apple: “With more than 200 new features, OS X Mavericks brings Maps and iBooks to the Mac, introduces Finder Tabs and Tags, enhances multi-display support and includes an all-new version of Safari.” Cool, ain’t it ? But this I like most: “The latest release […]
Split NSArray based on characters
Arrays are omnipresent. As I needed a snippet to make a string into an array of values, I thought would be helpful to share this for beginners. For example, take a string variable like, Create an array variable “array1” as:- I used the for loop to know the array1 values, which is displayed in Console […]
iOS 7 UIPickerView Simple Application
Recently I was asked by a friend to provide some support with UIPickerView in iOS 7. He was a bit puzzled by what it seemed to be the impossibility to pad the content of each picker view row to a certain distance from the left side of the UIPickerView. Basically, let’s consider the following example. […]
Usage of void in C
Going into some USB programming for a project I am into (on my Mac), I ran into this and I thought would be nice and useful to elaborate a bit. This is about void* pointers and callbacks in C. USB device discovery and probing under IOKit makes heavy use of callbacks, I wanted to write […]
Auto-increment versioning in XCode 5
Ok, this will be quick. There is no built-in feature or that supports automatic code versioning in XCode. I am talking about auto incrementing versions or build numbers in XCode plist, aka “CFBundleVersion” info.plist entry. Here’s a quick one for XCode 5. Make sure your target has an *Info.plist file. Add an entry there, as […]
Using LLDB Commands in XCode 4
The rationale for Apple’s move to LLVM and slowly parting with the aging GCC has a long history and is out of the scope of this brief tutorial on LLVM commands. The primary reason for switching from GCC to Clang — probably — is the incompatibility of GCC’s GPL v3 license with the goals of […]
NSString initWithBytes:length:encoding:
NSString initWithBytes:length:encoding instance method. A quick example. Uses a NSData object from the content of my blog’s first page and displays the string in an NSTextView outlet: The result: A variant, with a char array: The result:
CSS generators for fast web page styling
While revamping my blog, I ran over several CSS generators that are freely available on the web. These considerably speed up the process of styling your web. So I though would be nice to share some links. Some might be interested. Gradient CSS generators One of the best CSS generators is ColorZilla, available also as […]
Chasing Zombies in XCode 4
Ok, this will be a short one. Probably I will create a category like “code snippets and hints” to include all these small articles. This is about zombies in your coding projects and how to chase them. Enabling a project to trace zombies is different in XCode 4 than in previous versions. There is a […]