embedded

问题 I need to deal with a counter that gives me ticks for my application. The counter is 32bits so what i need to know is how to deal with it when it wraps. for example: I have a function that returns a (timestamp + shifttime) and i have another function that will return 1 or 0 depending whether or not the time has elapsed, but there could a possibility that that my counter will wrap how do I deal with this ?. Thanks Thanks a lot for all the responses guys. I will give more detail in this edit. I

问题 I work on an embedded system firmware code-basis which currently uses dynamic memory allocation. Now, all dynamic memory allocation shall be removed for reliability reasons. As a first step, I removed the _sbrk syscall implementation, such that all dynamic allocations fail to link. Since I compile with -ffunction-sections -fdata-sections and link with -Wl,--gc-sections I expect the link step to complete as long as no dynamic memory allocation occurs. (This worked for me in past C projects,

问题 i am attempting to integrate freeRTOS to my application that run on AT32UC3A0512. I downloaded a freeRTOS project example for EVK1100 (it Supports the AT32UC3A) and try to include the kernel source file so my application hierarchy looks like : src |ASF |APP_FOLDER |freertos |freertos-7.0.0 this hierarchy is different than the the hierarchy provided in the freeRTOS project example which looks like src |ASF |thirdparty |freertos |freertos-7.0.0 /********** freertos-7.0.0 is under ASF***********

问题 I want to generate a sine signal in C without using the standard function sin() in order to trigger sine shaped changes in the brightness of a LED. My basic idea was to use a lookup table with 40 points and interpolation. Here's my first approach: const int sine_table[40] = {0, 5125, 10125, 14876, 19260, 23170, 26509, 29196, 31163, 32364, 32767, 32364, 31163, 29196, 26509, 23170, 19260, 14876, 10125, 5125, 0, -5126, -10126,-14877, -19261, -23171, -26510, -29197, -31164, -32365, -32768, -32365

问题 I want to generate a sine signal in C without using the standard function sin() in order to trigger sine shaped changes in the brightness of a LED. My basic idea was to use a lookup table with 40 points and interpolation. Here's my first approach: const int sine_table[40] = {0, 5125, 10125, 14876, 19260, 23170, 26509, 29196, 31163, 32364, 32767, 32364, 31163, 29196, 26509, 23170, 19260, 14876, 10125, 5125, 0, -5126, -10126,-14877, -19261, -23171, -26510, -29197, -31164, -32365, -32768, -32365

问题 I'm doing some development in C with a STM32F107 chip and, at some point, the device began to reset when I call a specific function. I don't have a debugger and my debugging is just plain text over a serial port. I've used some other microcontrollers in which I was able to access a register to see the cause of the reset, but I can't seem to find an equivalent for this device. I'm aware of the hardware exceptions of the Cortex-M3, but I don't know if one of them is being triggered since I can

问题 I'm doing some development in C with a STM32F107 chip and, at some point, the device began to reset when I call a specific function. I don't have a debugger and my debugging is just plain text over a serial port. I've used some other microcontrollers in which I was able to access a register to see the cause of the reset, but I can't seem to find an equivalent for this device. I'm aware of the hardware exceptions of the Cortex-M3, but I don't know if one of them is being triggered since I can

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 7 years ago . Does anyone have especially good (or bad) experiences with any of the following embedded TCP / IP stacks? uIP lwIP Bentham's TCP/IP

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 7 years ago . Does anyone have especially good (or bad) experiences with any of the following embedded TCP / IP stacks? uIP lwIP Bentham's TCP/IP

问题 In reference to SO question: 52164135 The setup : I have a function which converts many double values into a predefined string. The input is a array of struct from which we concatenate two double values into a string. A double is of size 8 bytes or 64 bits and my MCU of operation is STM32, a 32 bit ARM micro-controller. An interrupt is also running parallelly. The data should look like: [[12.11111111,12.11111111],[12.22222222,12.22222222],...] But I get (very rarely): [[12.11111111,12