Hi, Iam working on LPC248 OEM board ,where iam testing the delays in RTX kernel.
In configuration file i set the value as shown below.
#define OS_TICK 10000
Can anybody explain what is the meaning of this?
In
os_dly_wait(100)
i kept 100 as sytem ticks.
The above delay work as 1sec delay.
My aim is to get the delay of 1sec ,what are the changes i needed in configuration file?
This is the number of micro-seconds per timer tick
If you make it 1000000 your tick would be 1 second (That is if your timer has enough range to handle this). 10ms is a fairly good default value for the OS_TICK. 1 could easily be too long.
os_dly_wait(100) is a delay of 1 second. Do you really want to change something so that you can do os_dly_wait(1) and have a 1 second wait?
I don't know your specific part, but Real-Time clocks are usually used to give you 1 second ticks and you could easily set up a mechnism to delay based on that clock (and still keep your 10ms timer for the OS)
Thanks Robert
What you said that is correct.
I took RTX_Conf_LPC23xx.c file from \Keil\ARM\RV30\Startup\Philips. In that file
#define OS_CLOCK 12000000 #define OS_TICK 100000
I have above values.Now iam running a task in which i kept the
os_dly_wait(100); //1sec delay
and printing a value which was incremented by one.
I have Embedded Artists' LPC2468 OEM Board with NXP's ARM7TDMI LPC24xx microcontroller.
I want to develop USB device stack on the board with KEIL uvison3 IDE using RTX kernel.
Iam unable to get 1sec delay with the above values.
Can you tell me what are the mistakes i have done while testing the delays?
With what you show, you should be getting a 10 second delay. Your OS_TICK is too large (It should be 10000) to have os_dly_wait(100) to give a 1 sec delay.
sorry Robert,
It is not working even if i changed to 10000. Iam getting two printed count values within 1 sec.
I have doubts on the below values
#define OS_TIMER 0 #define OS_CLOCK 12000000
How can i set the correct values.
The code is what i used for configuring the PLL
/* Fcck = 57.6Mhz, Fosc = 288Mhz, and USB 48Mhz */ #define PLL_MValue 11 #define PLL_NValue 0 #define CCLKDivValue 4 #define USBCLKDivValue 5 /* System configuration: Fosc, Fcclk, Fcco,Fpclk must be defined */ /* PLL input Crystal frequence range 4KHz~20MHz. */ #define Fosc 12000000 /* System frequence,should be less than 80MHz. */ #define Fcclk 57600000 #define Fcco 288000000 /* APB clock frequence , must be 1/2/4 multiples of ( Fcclk/4 ). */ #define Fpclk (Fcclk / 2)
This is what i have done in my code.
My goal is verifying the delays with real time clock. I want to see the printed count values for 1 sec which was compared to real time.
If i give any trouble sorry for that!!