RCC_APB1PeriphClockCmd on USART1

[nickabrham]

Posted on April 21, 2012 at 15:14

Hi,

According to the example code provide with the STM32F10x_StdPeriph_Lib_V3.5.0\Project\STM32F10x_StdPeriph_Examples\USART\Interrupt, the clock provided to both the USARTs  i.e.USARTy = USART1 and USARTz = USART2 is through RCC_APB1PeriphClockCmd using the command as in the code below.. ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// RCC_APB2PeriphClockCmd(USARTy_GPIO_CLK | USARTz_GPIO_CLK | RCC_APB2Periph_AFIO, ENABLE);   /* Enable USARTy Clock */   RCC_NVIC_IRQChannelSubPriority(USARTy_CLK, ENABLE);   /* Enable USARTz Clock */   RCC_APB1PeriphClockCmd(USARTz_CLK, ENABLE);  ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// Why is APB2PeriphClock not provided to USART1 e.g. RCC_APB2PeriphClockCmd(USARTy_CLK, ENABLE);? I am running this example on my STM3210E-EVAL at 72MHz. bye, Nick

[Tesla DeLorean]

Posted on April 21, 2012 at 15:49

void RCC_Configuration(void)

{   /* Enable GPIO clock */   RCC_APB2PeriphClockCmd(USARTy_GPIO_CLK | USARTz_GPIO_CLK | RCC_APB2Periph_AFIO, ENABLE);#ifndef USE_STM3210C_EVAL   /* Enable USARTy Clock */   RCC_APB2PeriphClockCmd(USARTy_CLK, ENABLE); #else   /* Enable USARTy Clock */   RCC_APB1PeriphClockCmd(USARTy_CLK, ENABLE); #endif   /* Enable USARTz Clock */   RCC_APB1PeriphClockCmd(USARTz_CLK, ENABLE); }

[nickabrham]

Posted on April 26, 2012 at 10:54 You are right its #ifndef USE_STM3210C_EVAL.I mistakenly took it #ifdef. Thanks. Regards, Nick.