Some ARM Cortex-M have a DWT (Data Watchpoint and Trace) unit implemented, and it has a nice feature in that unit which counts the execution cycles. The DWT is usually implemented on most Cortex-M3, M4 and M7 devices, including e.g. the NXP Kinetis or LPC devices.
DWT Cycle Count Register (Source: http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0489d/BABJFFGJ.html)
I’m pleased to announce that a new release of the McuOnEclipse components is available in SourceForge, with the following main features and changes:
SourceForge
When working and debugging a bootloader, debugging can be a challenge: During debugging the bootloader, a new binary gets loaded into the microcontroller address space which is unknown to the debugger. As soon as I step into the newly loaded binary, I only see assembly code, with that ugly “No source available” in Eclipse:
No Source Available, debugging in assembly
But wait: GDB is able to do pretty much everything you can imagine, so here is how to debug multiple binaries with GDB and Eclipse, and to turn the above into something which is easy to debug:
Debugging with Symbolics
To me, one of the most frustrating things working with ARM Cortex-M cores are the hard fault exceptions. I have lost several hours this week debugging and tracking an instance of a hard fault on an ARM Cortex-M0+ device.
In “Low Power LCD: Adafruit Breakout Board with Sharp Memory Display” I used a 96×96 Sharp Display (LS013B4DN04) with the Adafruit breakout board, but because that one seems to be EOL (End Of Life), I searched for a replacement. I have found the 128×128 pixel version (Sharp LS013B7DH03), and best of all, it is pin compatible :-). With a small tweak of the driver, it works :-):
Sharp Memory Display 128×128
One of the biggest road blocks (beside of closed source) using the BLE (Bluetooth Low Energy) stack from NXP is that it requires expensive tools to compile and build the stack. The good news is that I have now the NXP BLE stack for the Mikroelektronika Hexiwear ported to Eclipse and GNU gcc build tools for ARM 🙂
NXP BLE Stack in Eclipse
I’m using the NXP FRDM-K64F board in several projects: it is reasonably prices, has USB, Ethernet, micro SD card socket and connectors for Bluetooth classic and Nordic Semiconductor nRF24L01+ 2.4 GHz transceiver:
NXP FRDM-K64F Board
But one issue I have faced several times is that the board works fine while debugging and connected and powered by a host machine, but does not startup sometimes if powered by a battery or started without a debugger attached. I have found that the EzPort on the microcontroller is causing startup issues.
Time is passing by so fast, and the year end is approache fast! I’m pleased to announce that a new release of the McuOnEclipse components is available in SourceForge:
SourceForge
About a year ago, on December 7th 2015, Freescale and NXP have announced the completion of their merger. Now it is Qualcomm which wants to acquire NXP? It looks like these mergers are happening faster and faster. The reality is that merging products take more time than anticipated, and nearly one year later I can see the outcome of what comes out of the marriage between Freescale and NXP or between Kinetis and LPC: NXP has announced the MCUXpresso software and tools for Kinetis and LPC microcontroller:
Introducing MCUXpresso (Source: NXP video)
The year is coming to an end, the Holiday season is approaching. In case you are looking for a nice present: I have completed my version of a sand clock: a clock writing the time into sand:
Sandclock
If you are interested to build your own version, I have documented the different steps with tips and tricks…
MCU on Eclipse 