Multiple requests may be posted to the timer driver. For example, you can
make three timer requests in a row:

    Signal me in 20 seconds (request 1)
    Signal me in 30 seconds (request 2)
    Signal me in 10 seconds (request 3)

As the timer queues these requests, it changes the time values and sorts
the timer requests to service each request at the desired interval,
resulting effectively in the following order:

    (request 3) in now+10 seconds
    (request 1) 10 seconds after request 3 is satisfied
    (request 2) 10 seconds after request 1 is satisfied

If you wish to send out multiple timer requests, you have to create
multiple request blocks. You can do this by allocating memory for each
timerequest you need and filling in the appropriate fields with command
data.  Some fields are initialized by the call to the opendevice()
function.  So, for convenience, you may allocate memory for the
timerequest you need, call opendevice() with one of them, and then copy
the initialized fields into all the other timerequest.

It is also permissible to open the timer device multiple times.  In some
cases this may be easier than opening it once and using multiple requests.
When multiple requests are given, sendio() should be used to transmit each
one to the timer.

     multiple_timers.c 

If all goes according to plan, TimerIO[1] will finish first, TimerIO[2]
will finish next, and TimerIO[0] will finish last.