编译信息如下,请问该如何修改代码或者库文件?Rebuild target 'STM32F103C8x'compiling main.c...compiling gpio.c...compiling tim.c...compiling usart.c...compiling stm32f1xx_it.c...compiling stm32f1xx_hal_msp.c...compiling gizwits_product.c...compiling gizwits_protocol.c.....\Gizwits\gizwits_protocol.c(185): warning: #550-D: variable "lastReportTime" was set but never used static uint32_t lastReportTime = 0;..\Gizwits\gizwits_protocol.c(186): warning: #550-D: variable "currentTime" was set but never used uint32_t currentTime = 0;..\Gizwits\gizwits_protocol.c: 2 warnings 0 errorscompiling hal_key.c...compiling common.c...compiling dataPointTools.c...compiling ringbuffer.c...compiling stm32f1xx_hal_gpio_ex.c...compiling stm32f1xx_hal_tim.c...compiling stm32f1xx_hal_tim_ex.c...compiling stm32f1xx_hal.c...compiling stm32f1xx_hal_rcc.c...compiling stm32f1xx_hal_rcc_ex.c...compiling stm32f1xx_hal_gpio.c...compiling stm32f1xx_hal_dma.c...compiling stm32f1xx_hal_cortex.c...compiling stm32f1xx_hal_pwr.c...compiling stm32f1xx_hal_flash.c...compiling stm32f1xx_hal_flash_ex.c...compiling stm32f1xx_hal_exti.c...compiling stm32f1xx_hal_uart.c...assembling startup_stm32f10x_md.s...compiling system_stm32f10x.c...linking....\STM32F103C8x\STM32F103C8x.axf: Error: L6218E: Undefined symbol APBPrescTable (referred from stm32f1xx_hal_rcc.o).Not enough information to list image symbols.Finished: 1 information 0 warning and 1 error messages.".\STM32F103C8x\STM32F103C8x.axf" - 1 Error(s) 2 Warning(s).Target not created.Build Time Elapsed: 00:00:28相对应代码如下:stm32f1xx_hal_rcc.c53 extern const uint8_t APBPrescTable[8U]; /@@*!< APB prescalers table values */1190 return (HAL_RCC_GetHCLKFreq() >> APBPrescTable[(RCC->CFGR & RCC_CFGR_PPRE1) >> RCC_CFGR_PPRE1_Pos]);1202 return (HAL_RCC_GetHCLKFreq() >> APBPrescTable[(RCC->CFGR & RCC_CFGR_PPRE2) >> RCC_CFGR_PPRE2_Pos]);
PWM不是通过改变输出时间来控制LED亮度的吗?但是我用PWM模块接恒流驱动电源再接LED却发现改变PWM占空比并不能调节LED亮度,但是如果PWM模块串联分压电阻直连LED时,就能通过改变占空比改变LED亮度,但是此时通过LED的电流却又很小只有0.0几A,请问是不是恒流驱动电源不能使用PWM吗?应该换恒压驱动电源吗?
emwin除了stm32单片机可用其他单片机可以移植吗,或者可以移植其他ui吗
外观一模一样,都是0805,颜色也是深灰色,现在混在一起,要怎么区分,或者怎么测量,测量时电阻都是0欧
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