The Real Time Operating System, RTOS , uses a counter/timer to measure time and schedule system tasks at the requested interval. The counter has a reload value that is stored internally.

Two changes were made. The reload value is now stored in a variable that can be read at any time or used for other calculations.

A new function called Rts_Shift_Timer_Hardware has been added. It accepts an integer value that will be used to shift (offset), positive or negative, the nominal reload value for the timer. This effectively increases or decreases the time between timer events.

The shift time is passed to the function as an integer value that is internally limited to +-550. This limit corresponds to 10% of 1msec on the V5 XL hardware, 100usec. This will be used in Closed Loop controllers, in conjunction with EtherCAT. The Operating System timer on the 80386 must be synchronized with the timers that run on the EtherCAT devices that are using Distributed Clocks. This limit should be way more than is needed for the purpose that the function is being added for.

On the V5 XL hardware, each incremental value of the 550 limit is equivalent to approximately 0.18nsec.