#define CLK_FREQ ( 10000 ) #define CORE_FREQ ( 168000000 ) static void TIM_GPIO_Config( void ) { GPIO_InitTypeDef GPIO_InitStructure; // Enable GPIOA clock __HAL_RCC_GPIOA_CLK_ENABLE( ); // Configure PA8 pin as CLK output -- to CK Input GPIO_InitStru…

详解SPI中的极性CPOL和相位CPHA SPI由于接口相对简单(只需要4根线),用途算是比较广泛,主要应用在 EEPROM,FLASH, 实时时钟,AD转换器,还有数字信号处理器和数字信号解码器之间.   即一个SPI的Master通过SPI与一个从设备,即上述的那些Flash,ADC等,进行通讯.   而主从设备之间通过SPI进行通讯,首先要保证两者之间时钟SCLK要一致,互相要商量好了,要匹配, 否则,就没法正常通讯了,即保证时序上的一致才可正常讯.   而这里的SPI中的时钟和相位,指的…

老實說Real-time Clok這項功能,我也只有在PC和手機上有見過,其他的應用產品上我也很少見到. 言歸正傳在STM32F4 RTC這項功能在IC內部就有內建,在早期的8051是如果要做RCT是需要外接IC的. 而RTC只需要透過register setting就可以達成12 or 24 format也有提供2個 alrm interrupt, wake up. 由上面的Function diagram可以得知幾個重要的地方. 1. 紫色的框框是我們主要必須配置的Block 2. Alar…

//学习STM32F4的过程中关于时钟上面讲的比较好 特地转发与大家分享 STM32F4时钟设置分析 原文博客链接:http://blog.csdn.net/jdh99,作者:jdh,转载请注明. 环境: 主机:WIN7 开发环境:MDK4.72 MCU:STM32F407VGT6 STM32F4启动与STM32F10X不同,时钟已经默认配置好. 1.启动代码: 文件:startup_stm32f4xx.s <span style="font-family:KaiTi_GB2312;fon…

STM32F4 SPI with DMA A few people have requested code, so I thought I’d post the code showing how I’ve configured my GPIO, timer, SPI, DMA and NVIC modules, along with some explanation of how the system works.Note that I’m using the STM32F4 Standard…

78-WS2812-Library (STM32F4) //-------------------------------------------------------------- // File : stm32_ub_ws2812.h //-------------------------------------------------------------- //--------------------------------------------------------------…

VGA Output from STM32F4 Discovery board I love the web! There are so many cool projects out there, and some, with a tweak or two, get me where I want to go quickly, saving a ton of time and effort. Case in point: The Artektit page on VGA output using…

STM32F4 External interrupts Each STM32F4 device has 23 external interrupt or event sources. They are split into 2 sections. First interrupt section is for external pins (P0 to P15) on each port, and other section is for other events, like RTC interru…

STM32F4: Generating parallel signals with the FSMC The goal: The memory controller can be used to generate a "generic" 16-bit parallel data stream with clock. Address generation will be disregarded, as well as other control signals dedicated to…

http://stm32f4-discovery.com/2015/01/properly-set-clock-speed-stm32f4xx-devices/ I see that you have problems with your devices when you don’t know even (and you don’t even ask) on which speed your device is actually running. Speed of your device dep…