COMMENT
  ipulse1.mod
  Generates a train of current pulses
  User specifies duration of pulse, interpulse interval (ton and toff),
  and number of pulses.
  1/24/2002 NTC
ENDCOMMENT

NEURON {
   POINT_PROCESS Ipulse1
   RANGE del, ton, toff, num, amp, i
   ELECTRODE_CURRENT i
}

UNITS {
   (nA) = (nanoamp)
}

PARAMETER {
   del (ms)
   ton (ms) <0, 1e9>   : duration of ON phase
   toff (ms) <0, 1e9>   : duration of OFF phase
   num         : how many to deliver
   amp (nA)      : how big
}

ASSIGNED {
   ival (nA)
   i (nA)
   on
   tally         : how many more to deliver
}

INITIAL {
   i = 0
   ival = 0
   tally = num
   if (tally > 0) {
      net_send(del, 1)
      on = 0
      tally = tally - 1
   }
}

BREAKPOINT {
: printf("%g\n", t)
   i = ival
}

NET_RECEIVE (w) {
   : ignore any but self-events with flag == 1
   if (flag == 1) {
      if (on == 0) {
         : turn it on
         ival = amp
         on = 1
         : prepare to turn it off
         net_send(ton, 1)
      } else {
         : turn it off
         ival = 0
         on = 0
         if (tally > 0) {
            : prepare to turn it on again
            net_send(toff, 1)
            tally = tally - 1
         }
      }
   }
}