Category

Embedded Systems

Category

The I²C bus is the most popular of the three current serial EEPROM protocols because of its simplicity, high signal density, and unique write protect (WP) pin characteristics. This illustration shows the typical pin-out of an I²C device with pins 1 through 3 as address pins A0, A1, and A2. Pin 4 is designated as ground, Vcc, while pin 5 is the data line, SDA. The clock signal SCL is at pin 6, pin 7…

KWP2000/UDS devices are essential tools for anyone who wants to tinker with a vehicle’s onboard computer system. Whether you’ll use yours for chip tuning a hobby-racing vehicle or you need to equip your auto-shop business with better on-board vehicle diagnostics (OBD) programming tools. KWP2000 actually stands for Keyword Protocol 2000, which is the name of a set of communications codes employed by vehicle computers and systems that meet the OBDII regulatory standard. Diagnostic scanners and…

Using the  the current project aims to update a board through CANbus. The workflow: The first board has a firmware loaded into the SD Card. At the beginning it requests to transmit the firmware through CANbus. If the second board accepts the request, then the firmware is transmitted through the CANBus to the SD Card of the client. After the completion of the firmware transfer process, the system reboots itself and Stitch Bootloader flashes and loads…

Usually a firmware upgrade of the STM32FXXX boards are is not an easy task for customers. They have to plug the board and use several different tools to flash the memory. For that reason i have made a simple, effective and easy way to upgrade your firmware using an SD Card. The upgrade task is simple, just write your firmware in the first sector of the SD Card (use HxD application to perform this operation),…

Sometimes, we need an easy way to test and verify that our board works correctly, especially if we are using breadboards and cables. The following simple FreeRTOS thread is able to echo each incoming CAN frame. To use this thread you must enable FreeRTOS using the ST’s CubeMX software which will generate the appropriate startup source code and afterwards you have to include some extra libraries that can be found in the blog (please check…

In a previous post we saw a simple CAN library to handle the CAN interfaces of STM32 board. However one basic issue that we had to solve is the frames buffering (especially when we receive the frames). This issue came up by the processing time that each frame needs and the limitation that the receive interrupt routine should be as fast as possible. For that reason, the following source code presents an incoming CAN Frames…

Dynamic resources allocation has become even more attractive as a research direction with commodity computing gaining momentum and bringing new requirements regarding elasticity and flexibility and with the growing importance of cloud computing.  The aim is to deliver high-performance computational while leveraging on other aspects, such as energy consumption. Admittedly, heterogeneity comes at the cost of greater design and management complexity. A promising approach to address the difficulties posed by this scenario is to exploit…

The Controller Area Network (CAN, also known as CAN Bus) is a vehicle bus standard designed to allow electronic control units and devices to communicate with each other in applications without a host computer. STM32F779-Eval board has 3 CAN interfaces, however only the two of them have their own clock (master). For that reason the following library provides some C methods to activate and use those CAN interfaces. Beware that each CAN interface requires its…

I have recently been playing with UART and DMA, although i’m still getting my head around it,. DMA allows you to transfer large amounts of data through the system without getting the processor core involved. Rather than the CPU laboriously reading a byte, the writing a byte from one buffer to another, you’d give the DMA controller a pointer to the start of a source buffer, a pointer to the start of the destination buffer,…