# PocketCHIP or Pi?
by Seth Kenlon
When the Raspberry Pi hit the tech scene, it made a huge impact. It
wasn't the first tiny computer, by any means; there was the Chumby,
and the PogoPlug, and other hackable systems on chips, but nothing
quite so intentionally open and affordable as the Pi. You didn't have
to hack the Pi, you just put an OS on an SD card, booted, and you were
running an open source computer. And the computer you were running
only used a dozen watts of power, and wasn't encased in a bulky
plastic body that would end up in the landfill when you decided to
upgrade.
Best of all, it came at a time when the blossoming "maker" movement
just happened to be looking for processing power.
With the market primed for tiny computers, several similar projects
surfaced, and when [The Next Big Thing](
https://getchip.com/)
announced "the world's first $9 computer", called simply the "CHIP",
the idea got funded in days on Kickstarter.
The CHIP variant, the PocketCHIP, is an all-in-one $69 system
featuring a screen, the CHIP, an on-board battery, and a physical
keyboard.
The question is, how does the PocketCHIP compare to the ubiquitous
Raspberry Pi?
## All-in-One Hardware
### PocketCHIP
I took the PocketCHIP with me to the [All Things
Open](
https://allthingsopen.org) conference in 2016 as my conference
computer. I had to bring a laptop along for a presentation that I was
giving, because the presentation involved compiling and running
applications specifically on x86_64 architecture, but I only used that
for my presentation. Otherwise, I used my PocketCHIP for everything
from working online to taking notes during meetings and tech talks.
One of the distinct advantages of the PocketCHIP over a Pi is that the
PocketCHIP is designed as an all-in-one device. There are no hidden
costs to the PocketCHIP. You buy it, and you've got a self-contained
computing device, with a screen and a keyboard and WiFi and Bluetooth,
and power, and a repository full of all the best open source software
available.
Sure, you can buy a Pi and a screen and a battery pack and, unless you
get a Pi 3, a WiFi dongle and a Bluetooth dongle and you'll have
something approaching the PocketCHIP's portability. You might even go
to the trouble of [constructing a
case](
http://thingiverse.com/thing:2091747) for it. For an
off-the-shelf experience, though, PocketCHIP is the way to go if
you're looking for a "hiptop" computer.
Better yet, the PocketCHIP maintains the same modularity of the Pi,
because the PocketCHIP can be easily taken apart to free the CHIP from
the case. So if you only a portable hiptop device some of the time,
and you prefer the smaller form factor of just the CHIP board other
times, you get both with the PocketCHIP.
The glaring weakness in PocketCHIP's all-in-one design is the
keyboard. While it's a great idea to have a physical keyboard, and I
wouldn't give it up, I only consider it a backup keyboard at the best
of times. It's not that I mind typing on keys seemingly made of bubble
wrap, it's that key presses only register about 66% of the time. That's
within tolerance for small one-off tasks, but if you're writing code
or taking notes at a tech conference or writing an article (like this
one, in fact), it's a showstopper. I ended up resorting to a Bluetooth
keyboard within days of owning the PocketCHIP, and now I don't bother
taking one without the other. So much for all-in-one.
To be fair, though, I have the same feeling about touch screen phones
and tablets.
But wait, it gets worse. Unlike the standard CHIP, there's no GUI
interface for Bluetooth on the PocketCHIP. Pairing with a Bluetooth
device, even a trusted one, is a process that, in itself, requires
several commands. It's recursively maddening to be hindered by the very keyboard you're trying to replace, but it's Linux, so you can just script it:
#!/bin/bash
ARG="${1}"
help() {
echo "Connect a Bluetooth device to PocketCHIP"
echo "Usage: $ [MOD=1] ./blue.sh BLUETOOTH_ID"
echo "Optional: put your device ID into ~/.bluechip"
exit 0
}
xkbfunc() {
setxkbmap dvorak
xmodmap $HOME/Xmodmap.logitech
exit 0
}
if [ -e ~/.bluechip ]; then
ARG=`cat $HOME/.bluechip`
elif [ X"$ARG" = "X" ]; then
help
fi
echo "Using ID $ARG"
sudo systemctl start bluetooth || echo \
"Bluetooth already started or cannot be started."
sudo \
echo -e "power on\n connect $ARG \nquit" | bluetoothctl
xkbfunc
Aside from the keyboard, the PocketCHIP is exactly what it appears to
be: an ultra-portable pure-Linux machine. This isn't an Android phone
with a Linux chroot inside of it, this is Linux on a portable,
self-contained,
[Tricorder](
http://memory-alpha.wikia.com/wiki/Starfleet_tricorder)-sized
device.
### Raspberry Pi
The Raspberry Pi wasn't designed to be an all-in-one system. In fact,
you might argue that one of its strengths is its modularity. The Pi
itself isn't modular, it's a minimal configuration for a computer
system with all components either burned into its chip or soldered to
the board, but it's a computer that you can hook up to a tiny LCD
screen, an HD monitor, an array of LEDs, or any other peripheral you
please, or none of these things at all.
It's worth noting that the CHIP itself (without the case and screen
and battery that makes it a PocketCHIP) is equally versatile. But
there's at least one thing that sets the two apart: removable storage.
Every Raspberry Pi, aside from the Pi Zero (which was released after
the CHIP was Kickstarted, perhaps coincidentally?), has featured an SD
card slot. This makes it trivial to copy a Linux distribution onto a
Pi; `dd` it over to an SD card, resize the file system as necessary,
boot the Pi, and you're up and running.
It's not as easy on the CHIP or PocketCHIP. The storage is embedded,
meaning that to load a new OS on the CHIP, you have to flash the
CHIP's chip, much as you would a mobile phone.
My first experience with embedded Linux was the [Nokia
N800](
http://en.wikipedia.org/wiki/Nokia_N800). Being embedded, it
required flashing to get its Linux-based OS, Maemo, loaded or
updated. Flashing was done with a shell script from your computer to
your connected N800; it was simple and effective. Playing with mobile
phone OS images is trickier, since it usually requires a special
bootloader and Android Studio for the ADB toolchain. The PocketCHIP's
official method of flashing your device is done through your web
browser. As such, it feels almost familiar, or at least
non-threatening. Maybe it's over-simplified and clunky for a serious
geek, but for new users, it's a simple interface to freshen up or
rescue the PocketCHIP when something goes amiss. It's not an SD card
that you just pop in and go, but it's as close as you'll get with an
embedded OS.
### GPIO
At least for the Maker movement, one of the main appeals of the Pi is
its GPIO pins. If you've never used the GPIO pins, you've at least
seen them. They're the pins along the side of the board that allow the
Pi to interact with other electronic devices, whether it's an LED
light, an LED array, an off board micro controller, thermal sensors,
light sensors, or anything else you can imagine.
The CHIP has GPIO pins, too. In fact, the GPIO pins are what attach
the CHIP to the PocketCHIP board and provide the screen output and
keyboard input. You might think that means the CHIP's GPIO pins are
occupied when in PocketCHIP form, but amazingly the clever folks over
at The Next Big Thing thought of that already, and mapped new GPIO
pins along the top of the PocketCHIP case so that you still have
programmable GPIO pins no matter how you're using it.
I haven't done any serious work with the CHIP's GPIO pins yet, but
during testing, I found the GPIO pins to be a little more versatile
than those on the Pi. For instance, I was using the Pi for an art
project last year that triggered an array of LEDs and, in the mean
time, played a sound clip. Unfortunately, playing a sound on the Pi
interferes with the GPIO subsystem; the LEDs would light up, but
erratically, and the sound was often distorted (depending on how I
played it). The answer ultimately was to off board the LED control to
an Arduino, triggered by the Pi, and play the sound from the Pi. So
far, on the CHIP, I can get no such distortion. My caveat here is that
I no longer have access to the number of addressable LEDs that I was
using on the Pi, so it might be possible to break the CHIP's spirit
eventually, but so far I've been impressed with just how much the CHIP
can do all at the same time, without interference.
The Pi does have more GPIO libraries than the CHIP does, however, so
depending on what you're trying to achieve, there still may be a need
for a Pi or an Arduino. Luckily, the [Adafruit](
http://adafruit.com)
libraries have been ported to the CHIP, so for many of the common
electric components available online, there are ported libraries ready
for you to use.
Additionally, it's trivial to port most Python code written for a Pi
to a CHIP. Pin numbers need to be changed, and there's no need to
specify a pin mode as you do on the Pi so some lines get deleted, but
everything else is the same as long as you imported `RPi.GPIO as GPIO`
and `CHIP_IO.GPIO as GPIO` (a great argument for abstraction!).
## Battery Power
Speaking of great board design, the battery and power system on the
PocketCHIP is as modern and convenient as you could possibly hope
for. The battery's internal, insofar as it's on the inside of the
plastic casing. It can be swapped out as needed, since the case comes
apart pretty easily, but that's too much work. The great thing about
the PocketCHIP is that The Next Big Thing expertly engineered it
to receive power from either its on-board LiPo battery, or from its
USB port, if you plug in a mobile phone power pack or plug it into a
USB charger in a car, airplane, or at home.
What that means is that the PocketCHIP acts just like a laptop or
mobile phone when it comes to making sure you've got a charge. If
you're running low on power, you plug your PocketCHIP into a USB
charger or a power pack. If you need to get up and go, you unplug the
power and run off internal battery. All of this happens seamlessly,
without interruption.
Compare that to the Pi, and you'll understand why this is
exciting. There may be solutions I'm not aware of, but for a reliable
battery power flow on the Pi, my research has shown that a LiPo
interface must be used between the USB power pack and the Pi. As far
as I know, there's no way to attach a LiPo battery to the Pi, much
less charge it through one of the Pi's USB ports.
There have been several Pi hacks to extend battery functionality, and
that's one of the Pi's strengths: it is exactly what it claims to be,
an educational device that emphasizes and encourages homemade hacks to
make it into something bigger and better. It's not pre-packaged and
magical, it's raw and ready to be worked on.
## Ports
The PocketCHIP has three ports:
* USB
* Micro USB
* Audio
There's an HDMI adapter available for the CHIP. It's a sort of "hat"
(in Pi terminology) that plugs into the GPIO pins and provides an HDMI
output. With that many pins, it's not easy to put on or take off; I
got one for free as a Kickstarter reward, but I wouldn't recommend it.
The Raspberry Pi has a lot more:
* 2 USB
* Micro USB
* Audio
* Analogue Video
* HDMI
* Ethernet
That's a huge difference, and it potentially could be deal breaker
depending on your use case. For example, I have yet to even bother
using my CHIP as a dedicated server, while I've got a Raspberry Pi and
a Banana Pi in two different countries hosting websites. I could do it
with a CHIP, but I doubt I'll ever bother getting the USB-to-Ethernet
dongle I'd need to make it work the way I would expect.
On the other hand, I have yet to take a Pi to a coffee shop for an
afternoon of coding.
## Applications
When you boot the PocketCHIP, it boots to a custom launcher screen
featuring easy access to its 6 [default
applications](
https://docs.getchip.com/pocketchip.html#applications).
This launcher screen is customizable by modifying a JSON file hidden
away in /usr/share, but it's a hack. It's pretty obvious that the
PocketCHIP team didn't account for modifying the launcher screen,
although they have stated in their forum that a better solution is in
development. Rather than spend time hacking the launcher screen, I
mostly use either the Terminal to launch applications I've installed
with apt, or else use the launchers from /usr/share/applications
directly in the included File Manager.
The important thing is that applications are plentiful. You've got a
tiny screen to work with, and not all applications were designed for
that, but they're available, so you can install what you want,
configure those that need an allowance for the small screen, and use
what you need to use.
The problem is that the PocketCHIP is an embedded system. It has
limited storage space, and no builtin solution to install applications
to an external device. If you know enough Linux to hack around that,
then you can avoid running out of space for applications, but if you
can't be bothered to do that or you just don't yet know how, then
it's something to consider.
One of the most heavily promoted applications on the PocketCHIP is
Pico-8, a closed source game engine. I lobbied for this application to
not be pre-installed when it got introduced as a "bonus" during the
Kickstart campaign, but I was apparently in the minority. You can
uninstall it with `apt remove chip-pico-8` and save 2.5 MB whilst also
purging it of closed source. Replace with the excellent open source
alternative, [Love](
http://love2d.org), with `apt install love`, and
then hack the launcher screen to remove the PICO-8 entry.
The Pi has the advantage here. Not only doesn't it ship with
closed source applications, you get to pick the amount of storage you
use, so you can install everything you need, plus your user data.
## The all-important bottom line
The Raspberry Pi and the PocketCHIP are difficult things to
classify. Are they low-power and low-cost headless servers? are they
smart TV backends? are they controllers for robotics projects? retro
arcade game emulators? hiptop computers?
Well, they're all of these things.
If it's a mobile computing experience you're after, then the
PocketCHIP is a well-designed, expertly-engineered single board
computer ready to go. In a way, it's similar to buying
a [System76](
http://system76.com) Linux laptop: you buy the luxury of
not having to think about the hardware. You have everything you need,
and everything just works. Any hacking you do will be on code, not on
hardware.
The Pi is a little more raw. If you want it to be a mobile solution,
you have to build that yourself.
As a server, however, it's just the opposite.
I heartily recommend both.
