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linking arbitrary data using GCC ARM toolchain

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I want to link in raw binary data. I'd like to either put it at a particular address, or have it link to a symbol (char* mydata, for instance) I have defined in code. Since it's not an obj file, I can't simply link it in. A similar post ( Include binary file with GNU ld linker script ) suggests using objcopy with the -B bfdarch option. objcopy responds with "archictecture bfdarch unknown". Yet another answer suggests transforming the object into a custom LD script and then include that from the main LD script. At this point, I may as well just be using a C include file (which is what I am

Cycle counter on ARM Cortex M4 (or M3)?

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I'm trying to profile a C function (which is called from an interrupt, but I can extract it and profile it elsewhere) on a Cortex M4. What are the possibilities to count the number of cycles typically used in this function ? Function shall run in ~4000 cycles top, so RTC isn't an option I guess, and manually counting cycles from disassembly can be painful - and only useful if averaged because I'd like to profile on a typical stream with typical flash / memory usage pattern. I have heard about cycle counter registers and MRC instructions, but they seem to be available for A8/11. I haven't seen

GCC alias to function outside of translation unit -AKA- is this even the right tool for the job?

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问题 I'm working with FreeRTOS on an STM32 (Cortex-M3), and using the CMSIS library from ST to bootstrap everything. The CMSIS library defines the weak symbol SVC_Handler in the startup ".s" file. It must be overridden somewhere in order to get your ISR in the interrupt vector table. FreeRTOS defines vPortSVCHandler , which is the ISR I want to have handle the SVC interrupt. I would like to "glue" the two together using my application code (i.e. w/o modifyng FreeRTOS or the CMSIS source code). I

linking arbitrary data using GCC ARM toolchain

阅读更多关于 linking arbitrary data using GCC ARM toolchain

问题 I want to link in raw binary data. I'd like to either put it at a particular address, or have it link to a symbol (char* mydata, for instance) I have defined in code. Since it's not an obj file, I can't simply link it in. A similar post (Include binary file with GNU ld linker script) suggests using objcopy with the -B bfdarch option. objcopy responds with "archictecture bfdarch unknown". Yet another answer suggests transforming the object into a custom LD script and then include that from the

Cycle counter on ARM Cortex M4 (or M3)?

阅读更多关于 Cycle counter on ARM Cortex M4 (or M3)?

问题 I'm trying to profile a C function (which is called from an interrupt, but I can extract it and profile it elsewhere) on a Cortex M4. What are the possibilities to count the number of cycles typically used in this function ? Function shall run in ~4000 cycles top, so RTC isn't an option I guess, and manually counting cycles from disassembly can be painful - and only useful if averaged because I'd like to profile on a typical stream with typical flash / memory usage pattern. I have heard about