help with the clock!!!

QNX DEVELOPERS Porting
1

hi everyone!!

I’m porting device driver for vxwork to qnx 6.30 and i have problem with following:

/*
** Delaying execution
**
** os_get_time() Return system time since boot in ticks.
**
** os_delay_busy_us() Busy-delay for specified microseconds.
** Ties up the CPU it runs on.
**
** os_delay_thread() Delay for specified number of ticks. Must
** be running in a thread context and may be
** interrupted by signals.
**
** Returns TRUE if interrupted by a signal,
** otherwise FALSE.
*/

static void os_delay_busy_us(long x)
{

struct timespec t;
t.tv_sec=0;
t.tv_nsec=1000*x;
nanosleep(&t,NULL);

/* Counter Delay assuming that inner loop takes 1us */
/*int k,l;
for (k=0;k<x;k++)
for (l=0;l<2000;l++)
;
*/

}

#define os_ticks_per_second sysClkRateGet()

static unsigned long /* ticks */
os_get_time(void)
{
return (unsigned long) tickGet();
}

#define os_delay_thread(interruptable,x) taskDelay(x+1)
//-----------------------------------------------------------------------

sysClkRateGet();
tickGet();
taskDelay();

how to programming some similar or equivalent functions?

please!! help me!

thanks folks!!!

2

Have you tried compiling this on QNX yet? This should compile fine (i.e. no porting necessary).

3

yes that part does not need to be modified, yes works well, the problem is for the rest of the code.

4

But there is no other code (I don’t count 1 cover function and a macro as code)!

I suppose what you are asking is what are the equivalent of the following:

sysClkRateGet();
tickGet();
taskDelay();

The problem is I can’t give equivalents unless you specifiy the semantics of these calls. I can guess that tickGet() returns the current OS tick count; what I can’t guess is what exactly the tick count means on VxWorks (e.g. what is the period of a tick?).

I can direct you to the calls that I think might work for you. Look at:

ClockPeriod()
ClockTime()
SYSPAGE_ENTRY()

Hope that helps…

5

thanks!

/-------------------
sysClkRateGet() return the nurmer of ticks for second.

In QNX
A tick’s initial length is determined by the clock rate of your processor:
CPU clock speed: Default value:

= 40MHz 1 millisecond
< 40MHz 10 milliseconds

then there is 1000 ticks for second, that is true?

/------------------------------
tickGet() Return system time since boot in ticks, this function it’s use for compute the consumed time for some instructions.

I think that have use this function clock(), the logic is the same, is correct?

/-------------------------------------

taskDelay();

Can I use delay() ?

thanks!