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Dear All,
I am working my project of led Blinking.The controller used is arm7 LPC2214.Crystal is 11.0592mhz. Which works fine but only one problem is, to make it working i have to touch one of my Oscilloscope probe to crystal of controller.Then it start working.Also works well in keil debugger(internal) and on proteus.So please help me to solve this problem. The source code is as follows,
#include <lpc22xx.h> #include <stdio.h> #define VREF 3 #define Beep 0x00001000 #define LED1 0x00000800 #define LED2 0x00000400 #define LED3 0x00000200 #define LED4 0x00000100 #define CE 0x00000001 #define OE 0x00000002 #define WE 0x08000000 #define low IO0CLR = LED1 ; \ IO0CLR = LED2 ; \ IO0CLR = Beep ; #define hig IO0SET = LED1 ; \ IO0SET = LED2 ; \ IO0SET = Beep ; unsigned int val; unsigned long Fosc = 11059200; unsigned long Fcclk = 0; unsigned long Fcco = 0; unsigned long Fpclk = 0 ; void TargetResetInit(void) { Fcclk = Fosc * 4; Fcco = Fcclk * 4; Fpclk = (Fcclk / 4) * 1 ; MEMMAP = 0x2; //remap PLLCON = 3; if ((Fpclk / (Fcclk / 4)) == 1) VPBDIV = 0x10; else if ((Fpclk / (Fcclk / 4))== 2) VPBDIV = 0x11; else if ((Fpclk / (Fcclk / 4)) == 4) VPBDIV = 1; if ((Fcco / Fcclk) == 2) PLLCFG = ((Fcclk / Fosc) - 1) | (0 << 5); else if ((Fcco / Fcclk) == 4) PLLCFG = ((Fcclk / Fosc) - 1) | (1 << 5); else if ((Fcco / Fcclk) == 8) PLLCFG = ((Fcclk / Fosc) - 1) | (2 << 5); else if ((Fcco / Fcclk) == 16) PLLCFG = ((Fcclk / Fosc) - 1) | (3 << 5); PLLFEED = 0xaa; PLLFEED = 0x55; while((PLLSTAT & (1 << 10)) == 0); PLLCON = 3; PLLFEED = 0xaa; PLLFEED = 0x55; MAMCR = 0; if( Fcclk < 20000000) MAMTIM = 1; else if ( Fcclk < 40000000) MAMTIM = 2; else MAMTIM = 3; MAMCR = 2; VICIntEnClr = 0xffffffff; VICVectAddr = 0; VICIntSelect = 0; } void Delay (unsigned long a) { while (--a!=0); } void ledInit(void) { IO2DIR = 0xFFFFFFFF; IO2SET = 0; IO1PIN = 0x00000000; IO1DIR |= CE; IO1DIR |= OE; IODIR1 |= CE; IODIR1 |= OE; IO1SET |= CE; IO1SET |= OE; IO3DIR = 0xFFFFFFFF; IO3SET = WE; IO0DIR = LED1; IO0SET |= LED1; } static void ledOn(int led){ IO0CLR = led; } static void ledOff(int led){ IO0SET = led; } void delay(int d){ for(; d; --d); } int main(void) { ledInit(); TargetResetInit(); ledOn(LED2); ledInit(); while(1) { ledOn(LED1); delay(20000*8); delay(20000*8); delay(20000*8); delay(20000*8); delay(20000*8); ledOff(LED1); delay(20000*8); delay(20000*8); delay(20000*8); delay(20000*8); delay(20000*8); } }
Thanks & regards, Girish
You tested the crystal? You have equpiment to measure, and characterize, a crystal?
What results did you get?
What inductances did you measure? What static capacitance? What motional capacitance? What load capacitance? What drive level? What equivalent series resistance? What operating mode - fundamental or third overtone? What cut? What temperature range? ...
A crystal really is not just a magic device with a stamped frequency on the case. With wrong type of crystal and/or wrong burden capacitors in relation to processor, you can get into lots of troubles with oscillators that never starts, or starts sometimes, who only start within specific temperature ranges or depending on of voltage and noise levels etc.
So the startup code should match the recommended code from the processor documentation, but the capacitors, trace layout and crystal should also match the recommendations. And different processors are more or less sensitive to variations. Some processors can handle almost everything, while other processors have very narrow windows where the oscillator will work well - or at all.
Dear Sir,
As early stated i didn't went so deeply for testing crystal. I checked voltage across crystal and waveform of crystal.It was OK. If Agreed the crystal is faulty then the issue is if i program the hex file of old programmer in same IC it works successfully. Only if i program the same ic with hex file of my program then i have to touch the probe of oscilloscope to one of crystal pin then it starts working. How i can convinced to my senior on this issue?
I also grounded body of crystal. will you please help for sorting out this,
Thanks in advance,
Girish
I checked voltage across crystal and waveform of crystal.It was OK. yes, you said that already, to have "checked voltage across crystal" you have touched it with a scope probe
With Proper grounding and power traces as this board is of commercial product. that is no guarantee there are many shoddy "commercial products" how long are the traces to xtal and burden caps? how long traces to and what are the Vdd decoupling caps?
Erik
Another thing - does your processor always make use of an external oscillator, or does it boot with an internal RC oscillator like 23xx does? In that case - what code do you have that turns on the external oscillator and waits for it to stabilize before it may be connected for use by the core?
You post code for the PLL (seems to be different PLL settings for the two codes) but the PLL needs input. Is the oscillator spun up correcly before connected?
Just show him/her!
Get him/her to help you: he/she knows you, knows your project, can see your hardware, can probe it him/herself, can see your software, etc, etc - nobody on a forum has any of those advantages!