Raspberry Pi

1887 Articles

Building The Slimmest Raspi

July 17, 2014 by 28 Comments

slim_pi

[Colin], AKA [Domipheus], was working on a project to monitor a thermostat with a wall mounted Raspberry Pi and a touchscreen. Simple enough, but the Pi has a problem: The plugs are all around the perimeter of the board, and with a TFT touch screen shield, it’s a bit too thick to be wall mounted. What followed is a hack in the purest sense: [Domipheus] removed and relocated components on the Pi until the entire Pi/display stack was just a hair over 10mm tall.

A Raspberry Pi Model A was used for this build, meaning the Ethernet jack was gone, and there was only a single USB port to deal with. Still, the highest components – the RCA and audio jacks – were too tall and needed to be removed; they weren’t going to be used anyway.

After these components were gone, [Domipheus] turned his attention to the next tallest parts on the board: fuses, caps, and the HDMI port. For fear of damaging the surrounding components when removing the HDMI connector the right way, this part was simply hacked off. The large tantalum cap near the USB power connector was removed (it’s just a filter cap) and the large protection diode was moved elsewhere.

Slimming down a Pi is no good without a display, and for that [Domipheus] used this touchscreen thing from Adafruit. Things got a little complicated when the project required the ability to remove the LCD, but you can do amazing things with a DIP socket and a file.

The end result is a Raspberry Pi with touchscreen display that’s just a smidgen thicker than a CD case. It’ll fit right up against a wall in its repurposed enclosure, and the end result looks very professional.

[Thanks Luke via reddit]

Raspberry Pi Turns A Novelty Radio Into A Real Computer

July 15, 2014 by 32 Comments

picomp

[Strider19] remembers the 90’s, and a great little novelty radio he had back then. Shaped like a computer, the radio was a typical AM/FM affair, with the monitor serving as a speaker. His original radio was long gone, but [Strider19] was able to find a replacement on everyone’s favorite auction site. With the replacement radio in hand, he set his plan in motion: Turning it into an epic Raspberry Pi Case.

The Raspberry Pi fit great, but [Strider19’s] 3.5″ composite monitor didn’t quite make it. Following in [Ben Heck’s] footsteps, [Strider19] cut the LCD’s control PCB down to fit the case. A piece of clear polycarbonate protects the fragile LCD from poking fingers. The monitor’s button board, two USB ports, and an external composite input mounted nicely inside the former battery compartment at the rear of the CRT. There’s even enough room back there to hide a USB WiFi adapter.

The Raspi itself fit perfectly into the base of the radio, along with a DC to DC converter, USB hub, real-time clock module, and a whole bunch of wires used to extend the connectors.

The final result is awesome! Thanks to a request on [Strider19’s] Reddit thread, we have pictures of Doom running on a (former) radio.  Even Windows 3.1 runs under DosBox, though it took a bit of tweaking to get the display settings just right. Now [Strider19] just needs to figure out how to turn that tiny keyboard into a working model. We think some old school cell phone keyboard hacking may be in order!

 

The Raspberry Pi Model B+ Is Here (Again!)

July 14, 2014 by 105 Comments

Depending on who you believe, yesterday someone either broke an NDA or was the lucky recipient of an Element 14 shipping error. Nevertheless, we were lucky enough to get a glimpse at the new Raspberry Pi Model B+. Today, everything is live, and Adafruit has a great teardown of what’s new, what’s changed, and what’s completely different in this new board.

The biggest question about this new Pi was the CPU: the Broadcom SoC in the models A and B are looking a little long in the tooth right now, and an upgraded CPU would be a very, very welcome addition. There is no change. This is the same 700 MHz Broadcom chip with 512MB of RAM. There will not be a ‘magical, because you’re awesome’ RAM upgrade the original Model B saw early in production, either – there simply aren’t enough address pins in the SoC.

Despite not having an upgraded CPU, there are some neat features that addressed the complaints of the original Pi: The standard sized SD card socket is replaced with a microSD card socket that won’t stick out over the edge of the board. The ports are rearranged, with the analog video out on a TRRS plug with the audio. There are now four USB ports and an Ethernet port thanks to this chip, and mounting holes galore: they’re M2.5 holes in a square 58mm wide and 49mm high. Also included in the B+ is a completely redesigned power supply – the jumbo linear regulator is gone, replaced with an all-around better power supply.

The biggest change for anyone looking making a project with the Pi is the expanded GPIO header. This is a 40 pin header, with the ‘top’ pins identical to the original 26 pin header. Yes, all your existing Pi plates/shields/whatevers will still work. The new pins on this header include nine more GPIO pins, the I2S pins for the Wolfson audio card, and a pair of pins for an ID EEPROM. Connections to an ID EEPROM have been a feature of the BeagleBone for a while now, and this will allow the Pi to configure the appropriate I/Os and kernel modules at boot, depending on what Pi Plates are attached.

The best part about this is the price – it’s the same as the OG Model B. Using the same case as you old Model A or B is out of the question, but that’s totally what Kickstarter is for, right? You might want to grab one of those, because this is probably going to be the form factor for the upgraded Raspberry Pi 2.0 that will probably be released in a year or two.

ADC For Raspi Without Using An ADC

July 13, 2014 by 22 Comments

Schematic of ACD for a raspi

With all the amazing and wonderful things a Raspberry Pi can do, it is sorely lacking a dedicated ADC chip. Sure, you can wire up an ADC via SPI or even I2C with a little work, but still. It would be nice to have access to an Analog to Digital converter without having to go through the trouble. Fortunately, [Hussam] has figured out a way to do just this.

Using a comparator, two resistors, a single capacitor and a few lines of code, [Hussam] managed to get an active ADC working on his Raspberry Pi. He’s using the PWM1 and a passive RC filter to make a DAC. He then uses the comparator along with a ‘ successive approximation algorithm’ to complete the ADC.

[Hussam] mentions that the hack is not new, and this technique has been used before for microcrotrollers that lack a built-in ADC. But we are still impressed with his attention to detail in describing how to do this on a Raspi. Be sure to check out the link for full details, code, and an awesome description on how his algorithm works.

Introducing The Raspberry Pi B+

July 13, 2014 by 208 Comments

It looks like Element 14 screwed up a single shipment, because some lucky soul just received an unreleased model of Raspberry Pi. If you can believe the silkscreen, it’s called the Raspberry Pi Model B+, and while we have no idea what the chipset is, the layout and peripherals look pretty cool.

From the looks of it, this new board features four USB ports, a new, 40-pin GPIO header, and more screw holes that will allow you to secure this to anything. The analog video out is gone, and the SD card connector – a weak point of the original design – might be replaced with a microSD connector. Oh, every Raspi case that has ever been made? They won’t work.

Without booting this Raspi B+ there’s no way of knowing what the chipset is on this new board. The smart money is on the entire SOC being the same: basically, what you’re looking at is the same as a Raspberry Pi Model B, only with a few more ports.

There is no clue when these improved Raspis will be available, but the word “soon™” will probably appear on the Raspberry Pi blog shortly.

Thanks [John] for the tip.

EDIT: [feuerrot] is smarter than me and mirrored all the images in an imgur album.

 

Pi Musicbox 0.5 Released

July 13, 2014 by 4 Comments

Pi MusicBox Logo

 

Have an extra Raspberry Pi kicking around? Pi MusicBox provides a way to quickly turn it into a standalone streaming device that can fetch music from tons of sources. The latest release of Pi MusicBox adds a bunch of new features.

We took a look at this software over a year ago, and noted that it made streaming Spotify easy, and had support for controlling tracks using Music Player Daemon (MPD). The newest release supports AirPlay, DNLA, Google Music, SoundCloud, and several other music sources.

Since the analog audio output on the Pi isn’t great, Pi MusicBox includes support for a variety of USB sound cards. It’s also possible to use the HDMI port for digital audio output, which can be connected into your home theatre system.

If you want to build a standalone music device, this looks like a great place to start. The user community has built a variety of projects that run this software, which are featured on the Pi MusicBox homepage.

Pi-Powered Anti-Cat Trap Soaks Felines And Other Animals

July 10, 2014 by 52 Comments

[Joshua] has a problem with cats. They like pooping in his garden. He decided to take action with this awesome automated and humane cat trap.

Now just to clarify, he did attempt a few other alternatives before going all out in cat defense – the easiest solution would be to get a cat of his own, but alas, he’s not a cat person.

The system uses a Raspberry Pi in a waterproofed housing with a PiCam. He’s written some rudimentary code to make use of the PiCam Python Library which also allows him to record pre-cat-trapping footage, much for our enjoyment. When motion is sensed, the Pi trips a 24VAC solenoid water valve, which turns on the sprinkler and quickly soaks the intruder.

Stick around after the break for quite a few videos catching the furry little buggers in the act!

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