When developing firmware for an embedded project, it is important to know how much flash and SRAM the program is using. This allows you to make the best decision on whether the chosen MCU has sufficient resources for your needs. By default, GCC does not give any information regarding program size. However, GCC does include a utility that can help, sensibly it is called “size.exe” (or “arm-none-eabi-size.exe” for the embedded GCC version). If you run the program as follows: c:\iccv9cortex\gnuarm\bin\arm-none-eabi-size -A -x bin\Debug\Test.elf The /path/to/ is as installed by ImageCraft’s JumpStart C++ program, but any embedded GCC installation will have […]

C/C++ compilers include a set of standard functions to be linked with user programs. They are called libc and libc++ respectively. For GCC, they are also called glibc and glibc++ (in the rest of this post, I would use glibc to mean both glibc and glibc++). Most of the functions are directly callable by the user programs, e.g. printf, but some are internal functions known to the compiler to support operations not directly supported by the target hardware. For example, double precision floating point add. Traditional glibc is written for “big machines” such as Linux. For embedded use, it’s too

From time to time, we refresh the GNU Embedded ARM compiler (GCC) in our JumpStart C++ with the latest stable GNU release. Earlier in 2019, we refreshed GCC to the 2018-Q4 release. Surprisingly, our testing showed a failure immediately: objcopy.exe: 64-bit address 0x4b4fa300000000 out of range

The Microchip/Atmel SAMD21G18A is a powerful Cortex M0+ based MCU with 256K flash and 32K of SRAM. It’s used in the Arduino Zero as well as the Adafruit Metro and Feather lines of development boards, and is becoming a popular choice for users looking for a low cost powerful ARM Cortex-M MCU. The SAMD21G18A used in the Arduino and Adafruit development boards is programmed with a bootloader. The Arduino IDE uses this feature to download programs onto the MCU. However, instead of the limited Arduino IDE, you can instead use an advanced development environment such as JumpStart C++, Keil, or

In this article, we will examine some of the more popular Cortex-M hardware debug pods (also called debug probes), which are hardware devices necessary for debugging firmware on a Cortex-M based MCU. Overview of Debugging In the “good old days”, debugging an embedded system often meant the judicious use of printf to output debugging messages to a terminal. Fortunately, modern MCUs now come with hardware debug support that makes it easy to implement the core debugging features such as instruction breakpoints, and memory access. In the Cortex-M core specification, ARM Inc. includes a Coresight Debug Access Port (DAP) for just