{"product_id":"witty-pi-4-realtime-clock-and-power-management-for-raspberry-pi","title":"Witty Pi 4: Realtime Clock (RTC) and Power Management for Raspberry Pi","description":"\u003cp\u003eWitty Pi is an add-on board that adds realtime clock and power management to your Raspberry Pi.\u003c\/p\u003e\n\u003cp\u003eIt can define your Raspberry Pi’s ON\/OFF sequence, and significantly reduce the energy usage. Witty Pi 4 is the fourth generation of Witty Pi and it has these hardware resources onboard:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eFactory calibrated and temperature compensated realtime clock with ±2ppm accuracy.\u003c\/li\u003e\n\u003cli\u003eDedicated temperature sensor with 0.125 °C resolution.\u003c\/li\u003e\n\u003cli\u003eOn-board DC\/DC converter that accepts up to 30V DC.\u003c\/li\u003e\n\u003cli\u003eAVR 8-bit microcontroller (MCU) with 8 KB programmable flash.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eACCURATE REALTIME CLOCK AND ON\/OFF SCHEDULING\u003c\/h2\u003e\n\u003cp\u003eThe realtime clock (RTC) on Witty Pi 4 has been calibrated in the factory and Witty Pi 4’s firmware also makes temperature compensation for the crystal. This makes the RTC very accurate and the actual annual error is limited within ±2ppm. When your Raspberry Pi boots up, the time stored in the RTC will overwrite the system time. As a result, your Raspberry Pi knows the correct time even without accessing the Internet. You can schedule the startup and\/or shutdown of your Raspberry Pi, and make it a time-controlled device. You can even define a schedule script to schedule complicated ON\/OFF sequence for your Raspberry Pi.\u003c\/p\u003e\n\u003cp\u003eScheduling the ON\/OFF sequence for Raspberry Pi is the most popular feature of Witty Pi, and it is extremely useful for systems that powered by battery. By only turning on Raspberry Pi when necessary, the battery can be used way much longer with Witty Pi installed.\u003c\/p\u003e\n\u003ch2\u003eTEMPERATURE CONTROLLED DEVICE\u003c\/h2\u003e\n\u003cp\u003eThe temperature sensor on Witty Pi 4 has 0.125 °C resolution. The temperature data is used for compensating the crystal and make the RTC more accurate.\u003c\/p\u003e\n\u003cp\u003eYou can also specific the action (startup or shutdown) when temperature goes above or below the preset threshold. Which means you can also make your Raspberry Pi a temperature-controlled device.\u003c\/p\u003e\n\u003ch2\u003eDC\/DC CONVERTER AND E-LATCHING POWER SWITCH\u003c\/h2\u003e\n\u003cp\u003eWitty Pi 4 comes with a DC\/DC converter on board, which allows you to power your device with 6~30V power supply. You can also power your device with 5V via the USB type C connector.\u003c\/p\u003e\n\u003cp\u003eWitty Pi 4 also implements an e-Latching power switch, which is very similar to the power switch on your PC\/Laptop computer. You can gracefully turn on\/off your Raspberry Pi with a single tap on the button. The software running in background will execute the shutdown command before the power gets cut, this avoid the data corruption caused by hard shutdown.\u003c\/p\u003e\n\u003cp\u003eWitty Pi 4 supports all Raspberry Pi models that has the 40-pin GPIO header, including A+, B+, 2B, Zero, Zero W, Zero 2 W, 3B, 3B+, 3A+ and 4B. You will need to solder the 40-pin header to Zero\/Zero W\/Zero 2 W model beforehand, so they can make reliable connection with Witty Pi.\u003c\/p\u003e\n\u003ch2\u003eSINGLE I2C DEVICE\u003c\/h2\u003e\n\u003cp\u003eWitty Pi 4 uses MCU to emulate a single I2C device with default address 0x08, and also map all I2C registers in realtime clock and temperature sensor as virtual I2C registers in the same device. You can access all I2C registers in realtime clock and temperature sensor via the single I2C device emulated by Witty Pi 4.\u003c\/p\u003e\n\u003cp\u003eThe advantage of this new design is that Witty Pi 4 hides other I2C devices (realtime clock, temperature sensor) and becomes the proxy of them to talk to Raspberry Pi. Because the I2C address used by Witty Pi 4 can be changed to any value, you can always avoid the I2C address conflicting.\u003c\/p\u003e\n\u003ch2\u003eUWI SUPPORT\u003c\/h2\u003e\n\u003cp\u003eWitty Pi 4 is fully supported by UWI, and you can access you Witty Pi 4 on any device that have network access.\u003c\/p\u003e\n\u003ch2\u003eSOFTWARE INSTALLATION:\u003c\/h2\u003e\n\u003cp\u003eYou just need to run these two commands in your Raspberry Pi to install Witty Pi 3’s software:\u003c\/p\u003e\n\u003cp\u003e\u003ccode\u003epi@raspberrypi:~ $ wget https:\/\/www.uugear.com\/repo\/WittyPi4\/install.sh\u003c\/code\u003e\u003cbr\u003e\u003ccode\u003epi@raspberrypi:~ $ sudo sh install.sh\u003c\/code\u003e\u003c\/p\u003e\n\u003cp\u003eThe software and firmware of Witty Pi 4 are open-sourced. You can find the source code on \u003ca href=\"https:\/\/github.com\/uugear\/Witty-Pi-4\" target=\"_blank\" rel=\"noopener noreferrer\"\u003eGitHub\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePACKAGE CONTENT:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eEach Witty Pi 4 package contains:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eWitty Pi 4 board x 1\u003c\/li\u003e\n\u003cli\u003eCR2032 battery x 1\u003c\/li\u003e\n\u003cli\u003eM2.5 x 11mm Copper Standoff x 4\u003c\/li\u003e\n\u003cli\u003eM2.5 screws x 8\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSPECIFICATION:\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimension\u003c\/td\u003e\n\u003ctd\u003e65mm x 56mm x 19mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e23g (net weight without accessories)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMicrocontroller\u003c\/td\u003e\n\u003ctd\u003eATtiny841 (\u003ca href=\"http:\/\/www.uugear.com\/doc\/datasheet\/ATtiny841.pdf\" target=\"_blank\"\u003edatasheet\u003c\/a\u003e)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRealtime Clock\u003c\/td\u003e\n\u003ctd\u003ePCF85063A (\u003ca href=\"https:\/\/www.uugear.com\/doc\/datasheet\/PCF85063A.pdf\" target=\"_blank\"\u003edatasheet\u003c\/a\u003e), calibrated in factory.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTemperature Sensor\u003c\/td\u003e\n\u003ctd\u003eLM75B (\u003ca href=\"https:\/\/www.uugear.com\/doc\/datasheet\/LM75B.pdf\" target=\"_blank\"\u003edatasheet\u003c\/a\u003e)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDC\/DC Converter\u003c\/td\u003e\n\u003ctd\u003eMP4462 (\u003ca href=\"http:\/\/www.uugear.com\/doc\/datasheet\/MP4462.pdf\" target=\"_blank\"\u003edatasheet\u003c\/a\u003e)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMOSFET Switch\u003c\/td\u003e\n\u003ctd\u003eAO4616 (\u003ca href=\"https:\/\/www.uugear.com\/doc\/datasheet\/AO4616.pdf\" target=\"_blank\"\u003edatasheet\u003c\/a\u003e)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBattery\u003c\/td\u003e\n\u003ctd\u003eCR2032 (for time keeping when power supply is disconnected)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd rowspan=\"2\"\u003ePower In\u003c\/td\u003e\n\u003ctd\u003eDC 5V (via USB type C connector)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDC 6V~30V (via XH2.54 connector)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput Current\u003c\/td\u003e\n\u003ctd\u003eUp to 3A for Raspberry Pi and its peripherals\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStandby Current\u003c\/td\u003e\n\u003ctd\u003e~0.5mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd rowspan=\"2\"\u003eOperating Environment\u003c\/td\u003e\n\u003ctd\u003eTemperature -30°C~80°C (-22°F~176°F)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHumidity 0~80%RH, no condensing, no corrosive gas\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch2\u003eUSER MANUAL\u003c\/h2\u003e\n\u003cp\u003eMore information about this product can be found in its \u003ca href=\"https:\/\/www.uugear.com\/doc\/WittyPi4_UserManual.pdf\" target=\"_blank\"\u003euser manual\u003c\/a\u003e\u003c\/p\u003e","brand":"UUGear","offers":[{"title":"Default Title","offer_id":40032226148435,"sku":"WITTY_PI_4","price":29.95,"currency_code":"EUR","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0174\/1800\/products\/01_e679b66a-3c24-4f13-b766-71aa174b40cd.jpg?v=1655304185","url":"https:\/\/shop.pimoroni.com\/en-eu\/products\/witty-pi-4-realtime-clock-and-power-management-for-raspberry-pi","provider":"Pimoroni Ltd","version":"1.0","type":"link"}