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Update system_LPC8xx.c 

LPC812 was running at 12MHz on IRC. Added and fixed PLL activation to change the clockspeed into the expected 30MHz. Clock source is still the IRC. Selecting the 12 MHz XTAL clocksource should also work with the PLL.
Added MainClock to fix wrong setting of SystemCoreClock and allow the serial_api to use the correct clock.
pull/870/head
Wim 2015-01-27 21:00:01 +01:00
parent 74cd948470
commit 6fefefa3bb
1 changed files with 29 additions and 22 deletions
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51
libraries/mbed/targets/cmsis/TARGET_NXP/TARGET_LPC81X/TARGET_LPC812/system_LPC8xx.c
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@ -102,21 +102,26 @@
*/
#define CLOCK_SETUP 1 // 1 == IRC: 2 == System Oscillator 12Mhz Xtal:
//WH Fixed to use PLL
#if (CLOCK_SETUP == 1)
//use PLL for IRC
#define SYSOSCCTRL_Val 0x00000000 // Reset: 0x000
#define WDTOSCCTRL_Val 0x00000000 // Reset: 0x000
#define SYSPLLCTRL_Val 0x00000041 // Reset: 0x000
#define SYSPLLCLKSEL_Val 0x00000000 // Reset: 0x000
#define MAINCLKSEL_Val 0x00000000 // Reset: 0x000
#define SYSAHBCLKDIV_Val 0x00000001 // Reset: 0x001
#define SYSPLLCTRL_Val 0x00000004 // Reset: 0x000 MSEL=4 => M=5; PSEL=0 => 2P=2; PLLCLKOUT = (12x5) = 60MHz
#define SYSPLLCLKSEL_Val 0x00000000 // Reset: 0x000 Select IRC
#define MAINCLKSEL_Val 0x00000003 // Reset: 0x000 MainClock = PLLCLKOUT
#define SYSAHBCLKDIV_Val 0x00000002 // Reset: 0x001 DIV=2 => SYSTEMCORECLK = 60 / 2 = 30MHz
#elif (CLOCK_SETUP == 2)
//use PLL for XTAL
#define SYSOSCCTRL_Val 0x00000000 // Reset: 0x000
#define WDTOSCCTRL_Val 0x00000000 // Reset: 0x000
#define SYSPLLCTRL_Val 0x00000040 // Reset: 0x000
#define SYSPLLCLKSEL_Val 0x00000001 // Reset: 0x000
#define MAINCLKSEL_Val 0x00000003 // Reset: 0x000
#define SYSAHBCLKDIV_Val 0x00000001 // Reset: 0x001
#define SYSPLLCTRL_Val 0x00000004 // Reset: 0x000 MSEL=4 => M=5; PSEL=0 => 2P=2; PLLCLKOUT = (12x5) = 60MHz
#define SYSPLLCLKSEL_Val 0x00000001 // Reset: 0x000 Select XTAL
#define MAINCLKSEL_Val 0x00000003 // Reset: 0x000 MainClock = PLLCLKOUT
#define SYSAHBCLKDIV_Val 0x00000002 // Reset: 0x001 DIV=2 => SYSTEMCORECLK = 60 / 2 = 30MHz
#endif
//WH
/*
//-------- <<< end of configuration section >>> ------------------------------
@ -245,9 +250,11 @@
/*----------------------------------------------------------------------------
Clock Variable definitions
*----------------------------------------------------------------------------*/
//WH Added MainClock
uint32_t MainClock = __MAIN_CLOCK; /*!< Main Clock Frequency */
uint32_t SystemCoreClock = __SYSTEM_CLOCK;/*!< System Clock Frequency (Core Clock)*/
//WH Replaced SystemCoreClock with MainClock
/*----------------------------------------------------------------------------
Clock functions
*----------------------------------------------------------------------------*/
@ -278,48 +285,48 @@ void SystemCoreClockUpdate (void) /* Get Core Clock Frequency */
switch (LPC_SYSCON->MAINCLKSEL & 0x03) {
case 0: /* Internal RC oscillator */
SystemCoreClock = __IRC_OSC_CLK;
MainClock = __IRC_OSC_CLK;
break;
case 1: /* Input Clock to System PLL */
switch (LPC_SYSCON->SYSPLLCLKSEL & 0x03) {
case 0: /* Internal RC oscillator */
SystemCoreClock = __IRC_OSC_CLK;
MainClock = __IRC_OSC_CLK;
break;
case 1: /* System oscillator */
SystemCoreClock = __SYS_OSC_CLK;
MainClock = __SYS_OSC_CLK;
break;
case 2: /* Reserved */
SystemCoreClock = 0;
MainClock = 0;
break;
case 3: /* CLKIN pin */
SystemCoreClock = __CLKIN_CLK;
MainClock = __CLKIN_CLK;
break;
}
break;
case 2: /* WDT Oscillator */
SystemCoreClock = wdt_osc;
MainClock = wdt_osc;
break;
case 3: /* System PLL Clock Out */
switch (LPC_SYSCON->SYSPLLCLKSEL & 0x03) {
case 0: /* Internal RC oscillator */
SystemCoreClock = __IRC_OSC_CLK * ((LPC_SYSCON->SYSPLLCTRL & 0x01F) + 1);
MainClock = __IRC_OSC_CLK * ((LPC_SYSCON->SYSPLLCTRL & 0x01F) + 1);
break;
case 1: /* System oscillator */
SystemCoreClock = __SYS_OSC_CLK * ((LPC_SYSCON->SYSPLLCTRL & 0x01F) + 1);
MainClock = __SYS_OSC_CLK * ((LPC_SYSCON->SYSPLLCTRL & 0x01F) + 1);
break;
case 2: /* Reserved */
SystemCoreClock = 0;
MainClock = 0;
break;
case 3: /* CLKIN pin */
SystemCoreClock = __CLKIN_CLK * ((LPC_SYSCON->SYSPLLCTRL & 0x01F) + 1);
MainClock = __CLKIN_CLK * ((LPC_SYSCON->SYSPLLCTRL & 0x01F) + 1);
break;
}
break;
break;
}
SystemCoreClock /= LPC_SYSCON->SYSAHBCLKDIV;
SystemCoreClock = MainClock / LPC_SYSCON->SYSAHBCLKDIV;
}
//WH
/**
* Initialize the system