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Embedded Devices List

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ESP8266 - WiFi Module 802.11 b/g/n Wi-Fi Direct (P2P), soft-AP 1MB Flash Memory Integrated low power 32-bit CPU could be used as application processor SDIO 1.1 / 2.0, SPI, UART GP2Y0D805Z0F -   Digital Distance Sensor 5cm Output type: digital signal (low when detecting an object, high otherwise) G5306EADE632EB - BLE Module - iBeacon TTL data transparent transfer between a host Bluetooth device(IOS or Android 4.3) Default Baud Rate: 9600,8,1,n.    Coverage up to 60 meters Built in antenna GY-88 10DOF IMU - M otion Tracking Module 6-axis Motion Tracking device, that combines a 3-axis gyroscope, 3-axis accelerometer, and a Digital Motion Processor(DMP). 3-axis digital compass barometric pressure and temperature measure Gyroscope full-scale range of  ±250, ±500, ±1000, and ±2000°/sec (dps) Accelerometer full-scale range of  ±2g, ±4g, ±8g, and ±16g Wide Magnetic Field range: +/-8 Oe Pressure range: 300 to1100hPa  ...
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Programming Language Features

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C volatile Objects declared as volatile are omitted from optimization because their values can be changed by code outside the scope of current code at any time. The system always reads the current value of a volatile object from the memory location rather than keeping its value in temporary register at the point it is requested, even if a previous instruction asked for a value from the same object. So the simple question is, how can value of a variable change in such a way that compiler cannot predict. Consider the following cases for answer to this question. Global variables modified by an interrupt service routine outside the scope Global variables within a multi-threaded application https://www.geeksforgeeks.org/understanding-volatile-qualifier-in-c/ C storage classes there are four storage classes: automatic , register , external , and static .  auto The scope of automatic variables is local to the block in which they are declared, inc...
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Core Data

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Core Data is an object-graph management and persistence framework Core Data stack A Core Data stack is composed of the following objects: one or more managed object contexts connected to a single persistent store coordinator which is in turn connected to one or more persistent stores. A stack contains all the Core Data components you need to fetch, create, and manipulate managed objects. Minimally it contains: An external persistent store that contains saved records.  A persistent object store that maps between records in the store and objects in your application.  A persistent store coordinator that aggregates all the stores.  A managed object model that describes the entities in the stores.  A managed object context that provides a scratch pad for managed objects.  Managed object A managed object is a model object (in the model-view-controller sense) that represents a record from a persistent store. A managed object is an instance...
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