Cortex-M is a series of ARM processor cores intended for microcontroller applications. ARM licenses the design to third-party chip manufacturers and does not manufacture devices themselves. They are promoted as being suitable for low-power / cost sensitive applications that still need high ...

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54 views

RTOS for Cortex M4 with 802.15.4/6LoWPAN stack

I'm evaluating operating systems to use in an Internet of Things Project and I don't know what's the best way to proceed. I'm using a TM4C123GH6PM MCU with 32k RAM and a CC2520 802.15.4 transceiver, ...
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0answers
89 views

STM32 ADC: Multiple channels with different sampling rates

I am trying to figure out how the STM32 multiple channels ADC conversion works (regular group). Lets say I want to convert on two channels, channel 1 and channel 2, on ADC1 and the sampling rates are ...
0
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2answers
161 views

Assembler coding for ARM (Cortex-M0 and M3): is it possible/practical?

Unfortunately there are no questions on Stack regarding ARM and assembler at all. My concern -- is time critical devices. Let's take for an example one of my AVR-based device (program compiled with ...
0
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3answers
103 views

Do I need OS for ARM Cortex-M0(3)?

I'm a developer of control devices for switch mode power supplies which need to generate a PWM signal(s) with a frequencies about 100 kHz, measure analog signals, communicate vie USART, make ...
0
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1answer
88 views

SD Card Access Library

I am accessing my SD card using SPI. But I've found this to be slow and I am also sad that when there is a faster protocol already supported by my SD card I am using a slower version. Is there a C ...
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2answers
43 views

Why doesn't the MCU's pin go high on time?

I have a STM32F103 and I downloaded this program to it(a simple blink program): ...
1
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2answers
81 views

Measuring power consumption of a design ranging uW to tenths of mW

I want to measure the power consumed by my design ranging from uW to tenths of mW. Power values I wish could be recorded digitally so that I can use them for analysis later. May be another form is ...
0
votes
1answer
82 views

Code Security of ARM Cortex M4 MCU

What are the main methods the code inside a certain ARM Cortex M4 MCU (TI LM4F120H5QR etc) can be extracted after deployment? Is it possible to completely stop a third party from stealing the code ...
1
vote
1answer
85 views

External MMU for cortex-M

The Cortex-M processors are getting faster and more powerful. The Cortex-M7 has just been announced. Yet these cannot run Linux (other than uCLinux) because the chips lack an MMU - Memory Management ...
0
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1answer
114 views

ARM Cores Benchmark

I am taking some deep interest lately in the ARM architecture and there are many flavors of ARM out there....ARM7, ARM9, ARM11, ARM Cortex-A, ARM Cortex-M and etc. Are there any benchmarks of all the ...
1
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2answers
99 views

ARM cancel execution of pre-empted interrupts

I can't seem to find an answer to this in google or the Definitive guide... Is it possible to from one interrupt, cancel the return to any pre-empted interrupts? For example, I have an ISR which is ...
1
vote
1answer
51 views

What's the concept of these three options for configuring the memory of STM32?

I have read the STM32F10x Reference manual but a section about "Reading the Flash memory" is not clear to me, yet. I mean this part(page 59): I have several question: What's the Latency? in fact ...
0
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0answers
58 views

Differences between ARM, Cortex-Mx, MCU Manufacturer, Dev Board?

I trying to find out ways to send HTTP requests from a development board (EK-TM4C1294XL) and trying to find libraries and code samples and what not (note: this is not my actual question). I want to ...
0
votes
0answers
84 views

Can the Hidden Markov Model be run on an ARM Cortex-M3 processor?

I'm working on an algorithm for a device that utilizes the Hidden Markov Model (HMM) to crunch data and make its predictions. Can the HMM be run on an ARM Cortex-M3 processor running at 32MHz? How ...
1
vote
1answer
57 views

The same flag for an interrupt

I think I'm mixed up a bit in NVIC of stm32 MCUs. I took a look in the SPI.h of the STM32F10x standard peripheral library. I don't know that why while there is ...
2
votes
4answers
344 views

minimal ARM (cortex m0) board

First: I'm not a professional. I just want to know what is possible and if i'm on the right track. Second: I want a little microcontroller which just measures (for example) the temperature and send ...
3
votes
2answers
133 views

Moving code from an ARM M0+ to an ARM M4, what changes?

Say I have a very simple program that functions perfectly fine on a ARM Cortex M0+ processor. How much will I need to change in order for it to work on an ARM Cortex M4 processor, assuming they are ...
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votes
1answer
88 views

Recomendation for simple Cortex-M Flash Programmer [closed]

Looking for a recommendation for a simple, inexpensive, flash programmer for the Cortex-M - specifically the nRF51822. My project is ready to move into the short run prototype stage and I need to ...
1
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0answers
116 views

What is a Good Dev Board for Learning ARM for an Arduino User? [closed]

Lets start from my background: I am an Arduino veteran. I have played around with a lot of sensors and know a bit about hardware and software. I knew from the start that ARM platform has a lot of ...
1
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2answers
325 views

External Code Execution on ARM Cortex M

Is it possible to run code on the ARM Cortex M architecture from locations other than the onboard flash memory (such as another flash chip, SD card)? If so, how? If not, what microcontroller ...
8
votes
4answers
851 views

What are the differences between rand() function and RNG (Random number generator) peripheral?

I'm wonder for RNG (Random number generator) peripheral in STM32F4XXXX MCUs. look in this Reference Manual (page 748). On the other hand, we have the rand() function in stdlib library that do the same ...
0
votes
1answer
86 views

Writting Joystick drivers for ARM Cortex [closed]

I need to write a driver for Xbox360 joystick controller, using its module and everything. The idea isn't just take the code, I'm really interesting in the theory behind it. Does anyone have any ...
4
votes
3answers
522 views

Is there any difference between the assembly instructions of ARM MCUs from two different corporations?

I'm curious to know, are there any differences between the assembly instructions of ARM MCUs from two different corporation? For example between an Cortex-M3/4 of NXP and TI or ST or other ...
4
votes
3answers
1k views

STM32F4 - Floating point unit ( FPU )

I would like to know, what is the purpose of the special FPU unit, that is advertised with STM32F4 microcontrollers ? To quote this website : " The Cortex-M4 core features a Floating ...
3
votes
1answer
244 views

Can Tiva C run code from SRAM?

All I know is that although Cortex-M3/4 micros are Harvard architecture, they can run code from RAM, at least some implementations can (like STM32F4). Can Tiva C series microcontrollers execute from ...
0
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2answers
247 views

Force Cortex-M3/4 reset from assembly

I would like to force my STM32F4 to reset on fault, I tried to copy NVIC_SystemReset in assembly as : ...
8
votes
2answers
2k views

Endian problem on STM32

I'm using arm gcc (CooCox) to program an STM32F4discovery, and I've been wrestling w/ an endian problem I'm sampling with a 24 bit ADC via SPI. Since three bytes are coming in, MSB first I had the ...
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vote
0answers
106 views

Good (modern) sources on ARM Cortex hardware design [closed]

I am looking for some good resources on getting started in embedded hardware design with the ARM Cortex series. I'm primarily interested in the Cortex-M, Cortex-A, and Cortex-A50 series of chips. ...
0
votes
0answers
335 views

ARM SWDIO only works when touching 3V and SWCLK with fingers

I made a new STM32F2 prototype board and SWDIO debugging only works when I connect the Vinputref and SWCLK with my fingers. It was working fine on previous boards: it's the same circuit but different ...
3
votes
1answer
426 views

Does the CPU of an ARM Cortex M halt during flash self-programming?

Most ARM Cortex M MCUs do not feature EEPROM memory. Instead, persistent data can be written to the same flash memory that also holds the program. What is the state of the CPU during this ...
12
votes
3answers
2k views

What's really the difference between the Cortex-M series and the Cortex-R series?

It's interesting! I searched for find a clear article, but I couldn't find a clear article for this. Also I found this link: ARM Cortex-R and this link: Cortex-R Series but they are not exactly clear. ...
3
votes
1answer
5k views

STM32 GPIO Configuration

I am trying to figure out some online resource to figure out how to configure the GPIO Registers on an STM32F4 Cortex M4 board. I only have examples for the Cortex M4 ...
2
votes
4answers
254 views

Is simple voice synthesis (just digits 0-9) possible with Cortex-M0+ with 4kB flash?

I'm working on a little side project with the LPC810 (Cortex M0+ 32 bit ARM MCU, 8 pin DIP package, 4kB flash, 1kB SRAM). I need a UI to convey to the user a temperature setting. I only have about 2 ...
0
votes
1answer
277 views

ARM Cortex M3 (ATSAM3N4B) IACCVIOL Hard Fault

The ATSAM3N4B is an ARM Cortex M3 microcontroller from Atmel. I wanted to ask if anyone can help clarify the IACCVIOL Hard Fault processing. What I want is the infringing instruction address which ...
1
vote
2answers
515 views

What is the data register address for GPIO pin 21 Cortex ARM M0?

I need to find data register address for GPIO pin 21 Cortex ARM M0? I feel this question can need some background. I am learning embedded MCU programming and most sources mention that I need to find ...
2
votes
1answer
286 views

Cortex-M0 interrupt nesting

Question 1: When one interrupt handler is executed, will it be interrupted if another interrupt with the same priority occurs? Question 2: When one interrupt handler is executed, will it be ...
3
votes
3answers
703 views

Sleep on Arm Cortex

I'm trying to put a cortex m4 processor (m3 with dsp extensions) to sleep for a little less than a second. I want to be able to tell it to sleep, then a second later, or when a button is pressed, pick ...
0
votes
1answer
493 views

Clocking scheme for LAN8720A - Cortex M4

This is regarding a design choice involving LAN8720, specific to clocking schemes. We are interfacing an ARM cortex M4 (with inbuilt MAC) to the 8720 PHY via RMII in the REFCLKO configuration. In the ...
2
votes
7answers
270 views

Concurrent processes in MCUs

Is it possible to achieve FPGA-like concurrent functionality on, for example, ARM Cortex-4? If I have a process which does time-sensitive calculations and at the same time I would like to listen for ...
2
votes
2answers
2k views

STM32F4 Discovery demonstation not working anymore

I purchased a STM32F4 Discovery quite recently, and when I initially unboxed the board, I hooked it up to my Mac, and the already programmed in demonstration was working 100%. I was able to view the ...
3
votes
2answers
4k views

STM32F4 Discovery + Mac OS X + GCC + OpenOCD + Eclipse

I'm interested in buying an STM32F4 Discovery from ST Microelectronics. I'm using Mac OS X, 10.8 and would like to use a toolchain including GCC OpenOCD for debugging Eclipse IDE / IntelliJ IDEA ...
5
votes
1answer
545 views

Cortex-M4F FPU problems

I'm writing some code for a Texas Instruments Stellaris Launchpad board (a Cortex-M4F, the chip is a LM4F120H5QR). I'm using the IRMP library for infrared decoding, which works fine, as long as I ...
1
vote
0answers
315 views

Microphone and speaker types in a DSP audio processing application

I am attempting to design and build a PCB from scratch. The hardware is meant to be used in a DSP audio processing application. What I want to achieve is to be able to collect sound through a ...
1
vote
1answer
2k views

STM32 SysTick timer - Doesn't run the alarm event

I'm attempting to write an interrupt to keep basic time measured in ticks on an STM32F407VGT (Discovery Board.) My interrupt appears to run once (though I cannot be sure), but it then crashes/locks ...
5
votes
4answers
4k views

ARM Cortex (M3-M4): manufacturer and development IDE

I would like to do some MCU programming this summer and I've already had some unfortunate experiences with the STM32F4 DISCOVERY board, particularly the fact that it came without any (free) software ...