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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8
votes
4answers
532 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
43 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
397 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
381 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
106 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
votes
1answer
130 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 : ...
7
votes
2answers
534 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 ...
1
vote
0answers
68 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
123 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
185 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 ...
7
votes
3answers
574 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. ...
2
votes
1answer
2k 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 ...
1
vote
4answers
168 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
160 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
306 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 ...
1
vote
1answer
149 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 ...
2
votes
3answers
267 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
310 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
224 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
827 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
3k 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
394 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
227 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 ...
4
votes
4answers
3k 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 ...