BTP, Hardware, memristor

Memristors: Models, Window functions and their SPICE Simulations

This post mainly covers different famous memristor models, window functions along with their SPICE simulations(done on LTSPICE). The window function is used to add non-linearity at the boundaries. In contrast, Models are used to establish a linear/non-linear relationship between the rate of state change and the stimulus (current/voltage). Content: Models Linear Non-linear Threshold Macro-model Window functions Properties of window functions Types of window functions: Struckov Benderli Joglekar Biolek Prodomakis Jinxiang SPICE simulations Memristor Models Linear Ion drift Model (Ideal Model) In this model, there exists a linear relationship between the state derivative and the stimuli(Voltage/Current). It assumes that vacancies have…

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BTP, Hardware, memristor

Memristors : Motivation, Theory and Feasibility

Memristors, the fourth missing element after Inductance, Resistance, and capacitance, is nowadays a scorching topic of research among the electronics community. A large number of papers on its models, applications, and feasibility are now available. In this post, I’ll try to cover most of its background research: Content:- Introduction What are memristors? Characteristics of a memristor Transistor vs. memristor The polarity of a memristor and an analogy Memristor links to chaos theory?[TBD] Motivation well-known problems with present-day computers limitations of CMOS technology Moore’s soul at unrest Theory History Before HP After HP HP’s model Memristive systems Problems with Chua’s memristor…

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File system, Hardware, NAND/NOR

Effect of file-system on sd card’s performance

I had a task to compare different protocols( and their different implementations) like SD, SPI, SDIO(in FreeBSD’s MMCCAM implementation) by accessing SD Card. Now, for unbiased comparison, I must eliminate file system type in sd card from the equation. In this blog post, I’ll discuss/share my findings of the file-systems used for the card(SD and MMC) and how they affect its performance. So, let’s start with a very quick introduction to some basic concepts: Introduction MMC- Multimedia Card is a memory card unveiled in 1997 by SanDisk and Siemens based on NAND flash memory. eMMC is a regular MMC in…

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CAM, FreeBSD, Hardware, mmccam, SDIO, Software

Detailed SDIO protocol Implementation

Reference: Wikipedia, https://www.sdcard.org/developers/overview/sdio/sdio_spec/Simplified_SDIO_Card_Spec.pdf  SDIO cards are intended to provide high-speed data Input/Output on our regular sd card slot. SDIO cards are compatible with any sd card slot and will not cause any physical damage to the host if it’s not compatible with SDIO. When SDIO is plugged in an SDIO compatible host, in its early stage it is in low power mode and consumes very little current. The host identifies the SDIO card, it’s power requirement, it’s I/O capabilities, etc. If the host finds that the power requirement is manageable and there is a driver for the I/O functionality card…

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Hardware

Understanding SD, SDIO and MMC Interface

  TL;DR; MMC and SD-card have the same physical and electrical specifications but different software controls. They both are used as a storage device only. SDIO and SD-Combo cards, on the other hand, incorporate Input/Output functionality(like Bluetooth, Wifi, GPS, etc) without and with the storage facility respectively. So, a SD-Combo card can act as a wifi adapter along with a storage device. In this blog post, I will present a gist of the paper http://www.kaltech.co.il/pdf/Eureka_sd_wp1.pdf  (updated link). This is meant for anyone willing to understand how removable devices like sd card work and different protocols/functionalities they support. Secure Digital (SD)…

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Hardware, RTEMS, RTOS, Software

Building and testing RTEMS-libbsd for BeagleBone Black BSP

———————————————————————— Building and testing libbsd for BeagleBone Black BSP ———————————————————————— == Installation overview == === Initial setup === – Jump into your workspace and make a directory named sandbox This folder will contain all our project files – cd sandbox/ – export sandbox=$PWD – git clone git://git.rtems.org/rtems-source-builder.git – git clone git://git.rtems.org/rtems.git – git clone git://git.rtems.org/rtems-libbsd.git === Building desired toolset for ARM === – cd rtems-source-builder/rtems/ – ../source-builder/sb-check – ../source-builder/sb-set-builder –prefix=$sandbox/5 5/rtems-arm – cd $sandbox – export PATH=$PWD/5/bin:$PATH After having required toolchain, we can now proceed towards building our Board Support Package(BSP) === Building Beagleboneblack BSP === – cd $sandbox –…

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Hardware, Software

Introduction to RF communication

This post introduces the basics of RF communication along with various band specifications used for wireless communication. It also covers comparison of  different bands on basis of their data rates and other parameters. Content Introduction Available frequency Bands Types of RF communication Different wireless protocols Introduction Now a days, we are surrounded by a large number of wireless devices working on different protocols, on different frequency bands thus utilizing almost whole of the “Radio-wave” frequency spectrum. Adhering to it’s high density, complete frequency spectrum can be divided into different groups and each group can be further divided into different channels.…

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Hardware

DC motor selection for robotic applications

This post is mainly contributed by the members of the electrical team of ARES robotics. For designing a rover prototype, we have to select motors for applications like Robotic arm, wheels, etc.  This post aims to be a single guide containing all the information required for someone to choose an engine for an application. I’ll try not to cover motor constructional details, but rather their types, advantages, and application areas.   Type of DC electric motors used in robotic : Servo Stepper Brush-less DC Brushed DC Geared DC DC linear actuators Servo motors It is a self-contained electrical device that…

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Hardware, Software

Introduction to FRDM KL46Z and KDS

Outdated post alert: Sorry, this post is no longer being maintained. If you are loooking for some sample code for FRDM KL46Z visit: https://github.com/madaari/FRDM-KL46Z-developnment-board Year ago, i wrote a tutorial on getting started with freescale’s FRDM KL46Z development board. since then it was just a draft, today, i thought of updating and releasing it. So, here it is: But first of all, a very brief introduction of the development board and OpenSDA FRDM KL46Z Features MKL46Z256VLL4MCU – 48 MHz, 256 KB flash, 32 KB SRAM, segment LCD, USB OTG (FS) , 100 LQFP Capacitive touch slider, MMA8451Q accelerometer, MAG3110 magnetometer…

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