QNX RTOS v4 Knowledge Base
  
QNX RTOS v4 Knowledge Base
  
    
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            | Title | Hardware vs. software clock |  
            | Ref. No. | QNX.000009635 |  
            | Category(ies) | Configuration |  
            | Issue | We're having two QNX problems that seem to be similar: 
 1) We are changing the system time from the lower right-hand corner of the Photon GUI.  It accepts the change, but when we reset or power-cycle the computer, it forgets the change and goes back to the old time.
 
 2) We changed the system time using the clock_settime() function.  It accepts the change, but when we reset or power-cycle the computer, it forgets the change and goes back to the old time.
 
 
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            | Solution | Changing the time by clicking on the time in Photon changes just the software clock, not the hardware clock.  The same thing holds true for the clock_settime() function.  To change the hardware clock use the 'rtc' utility (see docs for rtc). |  |