Abstract: At step 40 the parameters for the jackpot are initialized, including a storage criterion and an award criterion. At step 41 the current value of the jackpot prize pool is calculated. At step 42 the CPU 2 checks whether the storage criterion has been met. If so, the currently accumulated value of the jackpot prize pool is stored at step 43 in memory 6 as a pending jackpot, along with the award criterion that is associated with that pending jackpot. The jackpot parameters are then redefined and the accumulation of as new jackpot prize pool is ready to commence. A number of pending jackpots may be concurrently stored in memory 6, each with an associated stored award criterion. At step 46 the CPU 2 determines if any of the award criterions that are associated with the pending jackpots have been met and if so, the associated pending jackpot prize is awarded at step 47 in accordance with a jackpot prize distribution scheme.

Abstract: At step 40 the parameters for the jackpot are initialized, including a storage criterion and an award criterion. At step 41 the current value of the jackpot prize pool is calculated. At step 42 the CPU 2 checks whether the storage criterion has been met. If so, the currently accumulated value of the jackpot prize pool is stored at step 43 in memory 6 as a pending jackpot, along with the award criterion that is associated with that pending jackpot. The jackpot parameters are then redefined and the accumulation of as new jackpot prize pool is ready to commence. A number of pending jackpots may be concurrently stored in memory 6, each with an associated stored award criterion. At step 46 the CPU 2 determines if any of the award criterions that are associated with the pending jackpots have been met and if so, the associated pending jackpot prize is awarded at step 47 in accordance with a jackpot prize distribution scheme.

Abstract: An embodiment of the method commences with some initialization steps 10 and 11, which include defining parameters for first and second jackpots. A loop commences at steps 12 and 13 at which current values of the first and second jackpot prize pools are calculated. At step 14 the CPU 2 determines whether storage criterion has been met. If so, the process flow moves to steps 15, 16 and 17. If not, the process flow moves directly to step 18. At step 15 the current value of the second jackpot prize pool is stored as a “pending prize”. Steps 16 and 17 effectively reset the second jackpot. At step 18 the CPU 2 determines whether the award criterion has been met. If not, the process flow loops back to step 12. If so, the first jackpot prize pool is awarded at step 19, along with one or more of any pending jackpot prizes, in accordance with a jackpot prize distribution scheme, then the pending jackpot prizes are deleted.

Abstract: The address of each track in a disk drive system is expressed in Gray code, and an appended bit of information is added to the Gray code, associated with the least significant bits thereof, the value of which is determined by the values of the most significant bits of the Gray code. The value of this appended bit is the same from Gray code to successive Gray code, as long as there are no changes in any significant bit between successive Gray codes, but the appended bit changes value when there is a change in a most significant bit between successive Gray codes.