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["Sun, Guanyi" <falcom.sgy@xxxxxxxxx>]

Hi Philipp,

According to your previous mail. In my understand, you mean I should
call sc_start in sc_main instead of my existed method to resum the
whole scheduler. Therefore i write code like following
sc_main()
{
     sc_start();
     while (sc_core::sc_get_status() == SC_PAUSED)
     {
         sc_start();
     }
}

It can not work. I think i still have some mis-understanding of
SystemC working principle and your meaning.  Could you give me some
example code to explain how to use sc_pause().

Thanks
Guanyi

On Thu, Feb 16, 2012 at 5:28 PM, Philipp A. Hartmann
<philipp.hartmann@xxxxxxxx> wrote:
> Guanyi,
>
> have a look at 1666-2011, section 4.3.4.2 (sc_start):
>  ...
>  "Function sc_start may be called from function sc_main, and only from
>  function sc_main."
>
> You are calling sc_start() from within a process.  It may be a bug in
> the proof-of-concept simulator to not detect this corner case, but you
> are definitely not supposed to do this.
>
> sc_pause() is meant to return control to sc_main() during the simulation
> to restart the simulation later (from sc_main).
>
> I did not check the rest of the code.
>
> Greetings from Oldenburg,
>  Philipp
>
> On 16/02/12 09:14, Sun, Guanyi wrote:
>> Hi all,
>>
>> Recently, i do an experiment of sc_pause(). I write following code
>>
>> // ===============example =====================//
>> SC_MODULE (TEST) {
>>    SC_CTOR (TEST) {
>>
>>      SC_METHOD(pause);
>>      sensitive << pause_event;
>>      dont_initialize();
>>
>>      SC_THREAD(test_thread_1);
>>      SC_THREAD(test_thread_2);
>>    }
>>
>>    void pause()
>>    {
>>         sc_pause();
>>         sc_start();
>>    }
>>
>>
>>    void test_thread_1()
>>    {
>>       for (int i = 0; i < 10; i++)
>>       {
>>           printf("in thread_1 @ %d ns\n",
>> sc_core::sc_time_stamp().value()/1000);
>>           wait(5,sc_core::SC_NS);
>>       }
>>    }
>>
>>    void test_thread_2()
>>    {
>>       for (int i = 0; i < 5; i++)
>>       {
>>           printf("in thread_2 @ %d ns\n",
>> sc_core::sc_time_stamp().value()/1000);
>>           wait(10,sc_core::SC_NS);
>>           sc_pause();
>>           printf("thread_2 pause @ %d ns\n",
>> sc_core::sc_time_stamp().value()/1000);
>>           sc_start();
>>           printf("thread_2 work again @ %d ns\n",
>> sc_core::sc_time_stamp().value()/1000);
>>       }
>>    }
>> // ===============example=====================//
>>
>> The result shows following
>>
>> in thread_1 @ 0 ns
>> in thread_2 @ 0 ns
>> in thread_1 @ 5 ns
>> thread_2 pause @ 10 ns
>> in thread_1 @ 10 ns
>> in thread_1 @ 15 ns
>> in thread_1 @ 20 ns
>> in thread_1 @ 25 ns
>> in thread_1 @ 30 ns
>> in thread_1 @ 35 ns
>> in thread_1 @ 40 ns
>> in thread_1 @ 45 ns
>>
>> The thread_2 does work again after first sc_pause() called.
>>
>> Then, i change the design
>>
>> // ==============new code =====================//
>>    void test_thread_2()
>>    {
>>       for (int i = 0; i < 5; i++)
>>       {
>>           printf("in thread_2 @ %d ns\n",
>> sc_core::sc_time_stamp().value()/1000);
>>           wait(10,sc_core::SC_NS);
>>           printf("thread_2 pause @ %d ns\n",
>> sc_core::sc_time_stamp().value()/1000);
>>           b_event.notify();
>>           printf("thread_2 work again @ %d ns\n",
>> sc_core::sc_time_stamp().value()/1000);
>>       }
>>    }
>> //===============new code ====================//
>>
>> This time the result like
>>
>> in thread_1 @ 0 ns
>> in thread_2 @ 0 ns
>> in thread_1 @ 5 ns
>> thread_2 pause @ 10 ns
>> thread_2 work again @ 10 ns
>> in thread_2 @ 10 ns
>> in thread_1 @ 10 ns
>> in thread_1 @ 15 ns
>> thread_2 pause @ 20 ns
>> thread_2 work again @ 20 ns
>> in thread_2 @ 20 ns
>> in thread_1 @ 20 ns
>> in thread_1 @ 25 ns
>> thread_2 pause @ 30 ns
>> thread_2 work again @ 30 ns
>> in thread_2 @ 30 ns
>> in thread_1 @ 30 ns
>> in thread_1 @ 35 ns
>> thread_2 pause @ 40 ns
>> thread_2 work again @ 40 ns
>> in thread_2 @ 40 ns
>> in thread_1 @ 40 ns
>> in thread_1 @ 45 ns
>> thread_2 pause @ 50 ns
>> thread_2 work again @ 50 ns
>>
>> This time, thread-2 can work normally. I still have no idea about this
>> after check the IEEE1666-2011 document. I want to know why and which
>> key information i am missing.
>
>
> --
> Philipp A. Hartmann
> Hardware/Software Design Methodology Group
>
> OFFIS Institute for Information Technology
> R&D Division Transportation · FuE-Bereich Verkehr
> Escherweg 2 · 26121 Oldenburg · Germany · http://offis.de/en/
> Phone/Fax: +49-441-9722-420/282 · PGP: 0x9161A5C0 · Skype: phi.har
>



-- 
Regards
Guanyi