RasPi.TV has Kickstartered a $12 “RasPiO Analog Zero” Raspberry Pi add-on board the size of an Raspberry Pi Zero. It offers eight 10-bit analog inputs.
The RasPiO Analog Zero has surpassed its Kickstarter goals, and is available through May 31 starting at 8 Pounds ($12). Designed for reading up to eight analog sensors simultaneously on a Raspberry Pi, the add-on board is matched to the size of the 65 x 30mm Raspberry Pi Zero. However, it plugs into any Pi with a 40-pin expansion connector, and can work with older 26-pin Pi models with the help of an adapter.
RasPiO Analog Zero with (left to right) Raspberry Pi A+, Pi 3, Pi 2, and at bottom, Pi Zero
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The RasPiO Analog Zero can be programmed with GPIO Zero, a set of Python APIs based on RPi.GPIO designed to control the Pi’s GPIO pins. GPIO Zero is now baked into Raspbian, so no extra firmware installs are required. The board also supports RPi.GPIO.
RasPiO Analog Zero on its own
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The RasPiO Analog Zero is the latest in a line of RasPiO products such as the 12-Pound RasPiO Duino. This Raspberry Pi add-on board offers Arduino Uno like circuitry. Once programmed by the Raspberry Pi, the RasPiO Duino can stand on its own like an Arduino board.
According to a RasPi.TV reply to a customer question, the RasPiO Analog Zero makes it easier to connect analog inputs compared to the RasPiO Duino. Instead of having to write two pieces of code — one for the Arduino MCU “to read the analog values and send them over the serial link, and one for the Pi that reads the values sent over the serial link,” you only need to write the Pi code, which can be as short as four lines, says RasPi.TV.
The RasPiO Analog Zero’s analog reference voltage for its eight inputs can be set to reference voltage at 3.3V or below. Although the board ships with an MCP3008 10-bit ADC chip, which is pin-compatible with the 12-bit MCP3208 that’s supported in GPIO Zero. Consequently, “if you really need those extra 2 bits of precision, you could swap out the chip,” says RasPi.TV.
Like the RasPiO Duino, the RasPiO Analog Zero offers a prototyping area, in this case with 54 points instead of 72. There’s also a GPIO breakout with labeled through-holes.
Add-ons include $3 “Portsplus” and $6 “GPIO Ruler” boards. Kits include a $36 Analog Experimenter’s Kit that combines the RasPiO Analog Zero with an array of jumper wires, temperature sensors, resisters, buttons, switches, and other components.
At left, Portplus (top) and GPIO Ruler (bottom); at right, 20×4 Weather Station/Voltometer/Digital Thermometer kit
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There are also two Weather Station/Voltometer/Digital Thermometer kits with either a 16×2 character display (32 characters) or 20×4 display (80 characters), starting at $39. The kits include the RasPiO Analog Zero, a display, plus two temperature sensors, two light sensors, and jumper wires.
Other Raspberry Pi add-ons with analog inputs include Pimoroni’s $13 Explorer HAT add-on.
The RasPiO Analog Zero is available through May 31 on Kickstarter, starting at $12. The board and most of the kits ship in July, although the weather station kit and discount bundles ship in September. More information may be found at the RasPiO Analog Zero Kickstarter page, as well as at RasPi.TV’s website.