All Questions
22
questions
2
votes
1
answer
2k
views
sbrk.c not seeing linker variable end
I am developing on SAM3X8E, I am using the GCC C++ compiler and atmel studio 7. I am trying to include the stdio library and I keep getting the error:
"undefined reference to end" in sbrk
...
- 557
0
votes
1
answer
111
views
Why are non-consecutive loads faster, even when the cache miss penalty is guaranteed to be zero?
Background:
I wrote a function in C and compiled it with arm-none-eabi-gcc (7-2018-q2-update).
The generated assembly code for the loop body looks like it should take 20 cycles per iteration,
...
- 1
0
votes
0
answers
189
views
cortex debug samd21 cortex M0+
Is anyone succesfully debugging a cortex M0+ board with vscode and cortex debug ? Let me explain, I have a personal borad build with an atsamd21e18a, when I start debug session it's ok debug starts ...
- 1,214
1
vote
0
answers
38
views
Flashed bootloader successfully but device doesn't show up in device manager
I've successfully compiled and flashed the arduino samd bootloader onto a custom atsamd21 board. I am using an external crystal oscillator (32khz) so I am not using the -DCRYSTALLESS option.
Now that ...
- 356
0
votes
1
answer
363
views
ATSAML21 Hardware Timer
I've been trying to configure & run hardware timer over SAML21 MCU to generate a 100ms delay i.e. ISR is supposed to hit at every 100ms. But it is observed that after starting the timer ISR is ...
- 11
0
votes
0
answers
240
views
DMA transfer corrupted by another channel (ATSAMC21)
I want to use DAM transfer for calculating CRC with ATSAMC21G17A MCU (E-revision).
I have already implemented 2 independent DMA channels controlling UART transfer, they are working good, I have no ...
- 53
0
votes
0
answers
159
views
Embedded Database on Cortex-M4 Microprocessor (Atmel SAM4S) [duplicate]
My team is working on a project that involves transmitting sensor data from a data logger module to a mobile application via Bluetooth. I am interested in finding a relatively fast, reliable way to ...
- 137
1
vote
0
answers
134
views
Hardware timer triggered analog-digital conversion on ATSAM4S
I have a problem with a ATSAM4S ADC unit triggered by Timer 0 (channel 1).
It seems that the ADC is triggered as fast as possible and blocks my whole application (OS is no longer operational due to ...
- 47
1
vote
0
answers
502
views
LwIP webpage with Post form - School project
For a school project we need to make a micro controller that takes the information off the CAN network and show these parameters on a web page.
I'm trying now to expand the project to make it also ...
- 9
0
votes
1
answer
1k
views
GPIO Pin Control SAMC21
i'm having trouble trying to use my new SAMC21 Xplained Pro from Atmel. I'm currently trying to understand the basics of Cortex M0+, but i stuck. I'm using ASF in Atmel Studio. I started from basic, ...
0
votes
2
answers
5k
views
SAMD21 clock configuration
I'm trying to configure my SAMD21 clock to go as fast as it can. So I'm using the internal 8 MHz oscillator to feed generic clock generator 1 (with a prescaler of 8) to generate a generic clock to ...
- 1,728
0
votes
1
answer
2k
views
Problems with code to send request and receive response over UART on Atmel SAM L21 Xplained Pro
I'm currently developing a system which involves sending a request string to a sensor device connected via UART to an Atmel SAML21 Xplained Pro board. I'm testing with an Arduino board as the "sensor ...
- 33
2
votes
1
answer
372
views
Cortex M0+ returns to wrong position in thread mode after interrupting sleep
I'm not sure if I'm missing something obvious here but has anyone else experienced any issues with the Cortex M0+ (or any of the Cortex M range) returning from an ISR to a somewhat random position in ...
0
votes
2
answers
1k
views
Cortex M0 doesn't enter sleep mode
Got a problem with the Atmel SAMB11 on an explained pro Devboard. I've loaded a quite simple example from Atmel, where a 32KHz Timer is initialized to wake up the µC from sleep and turn on a LED. ...
- 33
1
vote
2
answers
9k
views
Bootloader for Cortex M4 - Jump to loaded Application
I am using a Atmel SAM4E-16e on Atmel SAM4E-EK Board. I have written a bootloader for this configuration.
The bootloader receives the .bin-File via UART and writes it into Flash. This works without ...
- 31