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主题中讨论的其他器件：TIDA-010030你(们)好
我们将 MSP430Fr2115用于目标板。
参考板是 TIDA-010030。
我们尝试将时钟速度从12M 更改为24M。
(我们使用示波器来验证时钟速度值是否正确)
我们看到24M 时钟速度出现了两个问题
1：加载错误
将图像加载到目标板时、通常会发生错误。 (不是每次)
2：malloc 错误
甚至无法即时分配5个字节的内存。
每次程序开始初始化时都会发生这种情况。
我附加了时钟初始化代码和错误的两个映像
我的问题是24M 是该规格上的时钟速度，但我无法达到该速度。
有什么建议吗？
谢谢
void ClockInit()
{
//P3DIR bit 0 for MCLK
//P3SEL=01 for clock signal
//P3SEL0 |= BIT0;
//P3SEL1 = 0;
//P3DIR |= BIT0;
__bis_SR_register(SCG0); // Disable FLL
CSCTL3 = SELREF__REFOCLK; // Set REFO as FLL reference source
CSCTL1 = DCOFTRIMEN_1 | DCOFTRIM0 | DCOFTRIM1 | DCORSEL_7;// DCOFTRIM=3, DCO Range = 24MHz
//CSCTL2 = FLLD_0 + 30; // DCODIV = 1MHz
CSCTL2 = 731; //FLLD = 0 FLLN = 731 //24M
__delay_cycles(100);
__bic_SR_register(SCG0); // Enable FLL
Software_Trim(); // Software Trim to get the best DCOFTRIM value
CSCTL4 = SELMS__DCOCLKDIV | SELA__REFOCLK; // set default REFO(~32768Hz) as ACLK source, ACLK = 32768Hz
PM5CTL0 &= ~LOCKLPM5;
}
void Software_Trim()
{
#define MCLK_FREQ_MHZ 24 // MCLK = 24MHz
unsigned int oldDcoTap = 0xffff;
unsigned int newDcoTap = 0xffff;
unsigned int newDcoDelta = 0xffff;
unsigned int bestDcoDelta = 0xffff;
unsigned int csCtl0Copy = 0;
unsigned int csCtl1Copy = 0;
unsigned int csCtl0Read = 0;
unsigned int csCtl1Read = 0;
unsigned int dcoFreqTrim = 3;
unsigned char endLoop = 0;
do
{
CSCTL0 = 0x100; // DCO Tap = 256
do
{
CSCTL7 &= ~DCOFFG; // Clear DCO fault flag
}while (CSCTL7 & DCOFFG); // Test DCO fault flag
__delay_cycles((unsigned int)30000 * MCLK_FREQ_MHZ);// Wait FLL lock status (FLLUNLOCK) to be stable
// Suggest to wait 24 cycles of divided FLL reference clock
__no_operation();
while((CSCTL7 & (FLLUNLOCK0 | FLLUNLOCK1)) && ((CSCTL7 & DCOFFG) == 0));
csCtl0Read = CSCTL0; // Read CSCTL0
csCtl1Read = CSCTL1; // Read CSCTL1
oldDcoTap = newDcoTap; // Record DCOTAP value of last time
newDcoTap = csCtl0Read & 0x01ff; // Get DCOTAP value of this time
dcoFreqTrim = (csCtl1Read & 0x0070)>>4;// Get DCOFTRIM value
if(newDcoTap < 256) // DCOTAP < 256
{
newDcoDelta = 256 - newDcoTap; // Delta value between DCPTAP and 256
if((oldDcoTap != 0xffff) && (oldDcoTap >= 256)) // DCOTAP cross 256
endLoop = 1; // Stop while loop
else
{
dcoFreqTrim--;
CSCTL1 = (csCtl1Read & (~DCOFTRIM)) | (dcoFreqTrim<<4);
}
}
else // DCOTAP >= 256
{
newDcoDelta = newDcoTap - 256; // Delta value between DCPTAP and 256
if(oldDcoTap < 256) // DCOTAP cross 256
endLoop = 1; // Stop while loop
else
{
dcoFreqTrim++;
CSCTL1 = (csCtl1Read & (~DCOFTRIM)) | (dcoFreqTrim<<4);
}
}
if(newDcoDelta < bestDcoDelta) // Record DCOTAP closest to 256
{
csCtl0Copy = csCtl0Read;
csCtl1Copy = csCtl1Read;
bestDcoDelta = newDcoDelta;
}
}while(endLoop == 0); // Poll until endLoop == 1
CSCTL0 = csCtl0Copy; // Reload locked DCOTAP
CSCTL1 = csCtl1Copy; // Reload locked DCOFTRIM
while(CSCTL7 & (FLLUNLOCK0 | FLLUNLOCK1)); // Poll until FLL is locked
}
