Questions tagged [c]
C is an imperative (procedural) systems implementation language. It was designed to be compiled using a relatively straightforward compiler, to provide low-level access to memory, to provide language constructs that map efficiently to machine instructions, and to require minimal run-time support. C was therefore useful for many applications that had formerly been coded in assembly language. from http://en.wikipedia.org/wiki/C_(programming_language)
1,338
questions
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how to prevent pipelining optimizations in vivado hls
is there way to choose which optimizations vivado hls can use, specifically i want to disable pipelining option , i tried to use #pragma HLS occurrence , #pragma HLS pipeline off and it it doesn't ...
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37 views
Modifying Option Bytes at compile time
I need to modify the option bytes at compile time for STM32L0xx controller and generate the binaries i.e. .hex, .bin. could you please suggest a solution for the same. I amusing STM32Cube IDE for ...
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0answers
70 views
STM32 HAL_ADC_Start() ends with HAL_ERROR
I'm new to microcontroller programming and I have a problem I can't solve.
I am using STM32 Nucleo board L4R5ZI and I try to read the analog value on one of the pins, and then use the ADC to convert ...
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1answer
35 views
Bug and Best Practices for Interrupt Handling/Organization
I've read a few documents on best practices for interrupt handling and thought I was doing things correctly, ensuring the variable set in the ISR was declared volatile. In my code the interrupt ...
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1answer
70 views
How to implement C language driver for SPI peripheral [closed]
I have been implementing device driver for the SPI peripheral of the MCU in C language. I would like to exploit interrupt mechanism for reception and also for transmission.
As far as the reception ...
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1answer
55 views
Getting unexpected I2C Slave Address from a LSM9DS1 sensor and reading the wrong data from the register I just wrote in
I am using a STM32F030R8 nucleo board and a LSM9DS1 sensor. I'm just starting out learning about this stuff and I am having troubles reading from the sensor. Here are all the details about the problem ...
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1answer
117 views
Problem in c language [closed]
I need a and b value.
a=2;
b=a+=++a;
a+=-b;
Solution is:
a=0
b=6
Why is this the ...
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29 views
How to increase polling speed of data from external ADC (controller and ADC has SPI interface) without any external interrupt?
I have an an external ADC which has capability to sample data at 40Ksps and controller needs to poll the data from ADC. I am unable to get enough sampling rate by keepon calling it from while(1) loop (...
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1answer
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How to get rid of shift and logical operations
I am trying to upgrade an old firmware of a 32-bit MCU. The fw has many macros in it which uses various operations eg., logical shift etc. I want to replace these shift and logical operations. An ...
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22 views
How can I reset/stop a PWM timer using STM32F4 board
Hi I'm working with the STM32F4 board trying to make a servomotor do two movements (one side and the other).
This is my code so far:
...
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0answers
27 views
How to use ATMega USART in synchronous mode using XCK pin
I'm working on a project with ATMega64 and I have a problem with one of the USART interfaces which is going to work in synchronous mode.
when trying to send a test data like:
...
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36 views
Is my design for data reading over an I2C bus and writing back to UART good enough?
So I implemented drivers for I2C and USART using interrupts with some guidelines online, and was wondering if I can get some suggestions from a design point of view even though the code works (tried ...
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1answer
28 views
TIVA TM4C123G Driverlib Function Question
I have a question about how to use a basic GPIO function from the TIVA driver library to set an output pin high. See the below image for more detail.
The red underline on the code on the left hand ...
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1answer
56 views
TM4C123 Header File Problem
I'm having trouble getting a simple blinky project working using the on-board LED's on the TIVA TM4C123G evaluation board. I am using the header files from the driver libraries so I don't have to ...
0
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1answer
53 views
Approach to prevent Replay and spoofing attack on CAN protocol
I want to make an authentication system between 2 buses. In order to achieve that I use counter to avoid replay and hash to avoid spoof. The message must be sent in two phases. Is there any proper way ...
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1answer
26 views
Decoupling setting of specific bits (transfer mode, stream, channel) from the generic DMA_Init() function
So with regards to DMA drivers, what's the approach for configuring certain bits generic inside a function which could be reused for both TX and RX calls which would require different stream parameter ...
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1answer
30 views
STM32 Nucleo board, SD card displaying symbols instead of numbers
Devices: STM32F4
The SD is working and the data is saving on the SD, but the problem is that the integers are displayed as symbols in this SD. So I think that the problem is that the function I used ...
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0answers
87 views
Is my IIR implementation (in C) correct for this difference equation?
I recently started developing a digital regulator for a DCM boost (Digital regulator for DCM Boost - How does it relate to duty cycle?) And I've implemented the difference the following controller in ...
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0answers
34 views
Compiler settings to code in C with Proteus
I have made a circuit for a game called catch the light on Proteus. I have a C code for that. But I don't know how to set compilers and all that. I tried to add source code but due to some compiler ...
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2answers
97 views
PIC18F Rotary Encoder Code Help XC8
I'm trying to interface a rotary encoder with my pic18f4550. Just trying to get it to increase/decrease the variable output and then display that value through the ...
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2answers
353 views
Efficient way of writing to flash memory without losing data
For my project, I am writing some code that gets some results and I want to store these results on external flash memory. The external flash memory in question is a MX25R8035F. I found that writing ...
2
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1answer
64 views
Making use of the serial data received via UART - a few concerns [closed]
So I have been finally able to send and receive data serially via usart, but now I'm thinking of getting something useful out of it.
One thing that I do plan on doing is maybe take in the input, ...
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2answers
41 views
How is clock bus different than peripheral clock in STM32?
Been looking to clarify this confusion: how is the clock that a specific peripheral is on (APB1, APB2 etc) different than the peripheral clock itself?
Say, I2C1 ...
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21 views
Is there any standard way of defining respective data structures to read the sensor data into?
So I have been wondering about the standard way of structuring your files/code when it comes to reading data from the driver file.
So what I now have is a buffer that's supposed to store the data that ...
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2answers
52 views
Set multiple pins to different GPIO ports
I am using an STM32F4 discovery board and I have the following array v
...
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2answers
74 views
How to structure an application, and driver code for UART - the concept of decoupling the data [closed]
So I'm writing drivers for UART on STM32 and even though I kind of have an idea on laying out the structure, I'd still want to clarify prior to implementing, and also considering how essential it is ...
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9answers
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Does the “Avoid using floating-point” rule of thumb apply to a microcontroller with a floating point unit (FPU)?
As a rule of thumb, I try to avoid using floating-point in my embedded system codebase.
Floating-point variables are:
Computation-intensive
Not atomic (can cause problems in an RTOS application or ...
0
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1answer
37 views
How to use UART interrupts for PIC24 with MCC?
I'm using UART6 to interrupt my program whenever it receives an incoming string. I'm using the MCC to generate functions that I can use but I'm not sure how to call my interrupt function. Here is my ...
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0answers
65 views
USB Audio device won't open in windows
I'm working on a simple USB audio input device based on the Microchip/Atmel ATSAMD21. The descriptors identify it as a single channel microphone with a single feature unit for volume control.
As I ...
0
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1answer
84 views
STM32F103 bxCAN not working
I'm trying to make use of the bxCAN of STM32F103C8 on a bluepill but it doesn't work and I don't know what is the problem.I'm using the hal API
here is the main code in the while loop
...
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0answers
23 views
UART Overrun Error handling when transmitting data onto a terminal (lpc2138)
I am making a driver code for lpc2138. Currently I need to read the voltage on a potentiometer with the ADC and with the use of timer, print it onto a terminal in regular intervals. There are also ...
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2answers
73 views
STM32 I2C only sends address
Hello I am trying to communicate with TI BQ28Z610 by using Nucleo-F746ZG. All I do is trying to read data from TI chip. I am sending 0x08 to slave address 0x55.I2C frequency is 80kHz and pull ups are ...
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2answers
136 views
Creating a memory mapping to peripheral memory on STM boards
I am trying to find a way to load/execute code that is stored on an external SRAM chip without having to load it to the microcontroller internal memory. I'm not 100% sure of the name for what I'm ...
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2answers
62 views
How to go from specs/requirements to design, architecture, code, tests, documentation for embedded systems? [closed]
How do professional embedded systems engineers design, architect, code, test, document systems?
Any good examples, libraries, resources that showcase the process of going from specs/requirements to ...
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0answers
51 views
What's the way of passing a pointer from application file to driver HAL file that contains interrupt handler?
So there's a static pointer inside hal.c that stores a reference to the pointer being passed in from app.c, but having a ...
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1answer
73 views
Saving a variable between reboots on a microcontroller without using flash memory
I am developing a bootloader and have some trouble jumping from the bootloader to the application. As far as I can see the problem is because I am doing certain initializations in the bootloader which ...
1
vote
1answer
34 views
While loop for function call for enabling I2C interrupts seems to be behaving weirdly
Trying to understand why the while loop is behaving weirdly.
HAL_MasterReceiveInterrupt() enables the control bits for I2C and ...
0
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1answer
57 views
Incorporating RTOS into a simple sensor interfacing project for learning purpose
I am trying to switch to embedded from a software test role, and been working on learning about STM32, and almost finishing up writing drivers for I2C which I used for interfacing with a sensor.
I ...
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1answer
39 views
Getting a NACK after reading 1 byte from MCP9808 temperature sensor
I am implementing drivers for I2C interrupts for STM32F401RE and looks like the API for transferring the data seems to work. But for receiving, I see that I'm only able to receive one byte.
I am ...
0
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1answer
56 views
Unified struct in C to represent multiple sensor data
Working on desginging APIs for sensor events. I was wondering if there is a way to represent different type of sensor readings into a unified struct in C ?
For example a accelerometer'e reading ...
3
votes
2answers
193 views
How can I design a low pass filter using Z transform in Microcontroller?
I have generated a signal which is a mixture of 50 Hz and 250 Hz sine waves using a microcontroller and DAC. Check the screenshot of the excel file:
The values of row 4 (i.e. f1+f2) are feed to an 8-...
3
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0answers
94 views
Getting an ACK failure right away after writing slave address in interrupt mode for I2C [STM32F4]
I see that once slave address is written in the interrupt handler, I get an ACK Failure right away, but when I do the same thing with polling approach, I do get an ACK and goes on to read off the ...
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0answers
52 views
Capture GPIO pin values with STMA32 and DMA
I am trying to capture all GPIO_C port pin values at a time when PA0 pin goes low. I am using STM32F091RC micro-controller. But I cant figure out why ...
2
votes
1answer
73 views
Stack error when jumping from bootloader to application
I have been trying to jump from my bootloader to an application for a while now but I can not figure out what is going wrong. I am hoping someone here might be able to help me.
I am using Texas ...
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0answers
51 views
Imprecise bus error when setting Vector Table Offset Register. TI CC2652
I am developing a bootloader and want to jump to the application.
I am new to this so I am not entirely sure I am doing it right, but as far as I know I have to change the value stored in the VTOR (...
0
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1answer
63 views
CAN bus malfunction on STM32F3
I create applications for STM32 F303RE for communication with the instrument panel. I managed to connect everything but I have some problems. I'm not sure if it's due to bad code or good performance. ...
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1answer
64 views
NAK in CAN bus for STM32F3 uC
I have a problem with the NAK on the CAN bus. On STM32F303RE I wrote a code for communication via CAN bus with car dashboard (Instrument Panel Cluster). The communication works, I manage to receive ...
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vote
1answer
53 views
Checking interrupt flags for UART data receiving and transmitting on STM32
I'm trying to develop a UART receiver/transmitter for an academic project. For now i developed the UART continuous data receiving part and it works quite well. Here is the code:
Interrupt file:
...
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0answers
29 views
How can I add a SVCall handler to the Vector Table of a CC2652 device
According to the CC26xx Driver Library documentation there are two options for adding interrupt handlers, one dynamically and one statically. The static registration of handlers seems to be the ...
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0answers
39 views
Proteus gives unrecognized attribute 17 for stm32 Hello World in C
Here is my simple C program for the stm32, I tested it on QEMU, it flashes the led successfully. But when I try to load the main.elf file into the MCU on Proteus, I ...
