Memory and force output management for a force feedback system

A method for managing the storage of force effects in a force feedback system, the force feedback system including a force feedback device connected to a host computer, the method comprising:

• receiving a force effect create command by a driver running on said host computer, said command sent from an application program running on said host computer, said force effect create command instructing that particular force effect data for a particular force effect be stored in memory local to said force feedback device;
• determining whether said local memory has sufficient space to store said particular force effect data;
• if said local memory does have said sufficient space, sending said particular force effect data to said force feedback device to be stored in said local memory;
• and
• if said local memory does not have said sufficient space, storing said particular force effect data in a cache implemented in memory of said host computer instead of said local memory.

An apparatus for managing the storage of force effects in a force feedback system, the force feedback system including a force feedback device connected to a host computer, the method comprising:

• means for receiving a force effect create command by a driver running on said host computer, said command sent from an application program running on said host computer, said force effect create command instructing that particular force effect data for a particular force effect be stored in memory local to said force feedback device;
• means for determining whether said local memory has sufficient space to store said particular force effect data, wherein if said local memory does have said sufficient space, said particular force effect data is sent to said force feedback device to be stored in said local memory, and wherein if said local memory does not have said sufficient space, said particular force effect data is stored in a cache implemented in memory of said host computer instead of said local memory;
• and
• means for receiving a command by said driver from said application program to output said particular force effect to a user of said force feedback device, wherein if said particular force effect data is stored in said cache, said driver swaps said particular force effect data with loaded force effect data in said local memory and instructs said force feedback device to output said particular force effect.

A method for outputting force effects from a force feedback device coupled to a host computer, the method comprising:

• receiving a force effect play command from said host computer, said play command instructing that a particular force effect be output by said force feedback device, said particular force effect being stored as data in a memory local to said force feedback device, said local memory also storing data for at least one other force effect;
• designating in a playlist in said local memory an identification of said particular force effect;
• examining said playlist to determine which of a plurality of stored force effects are designated to be output;
• determining a force based on said force effects designated in said playlist and outputting said force to a user of said force feedback device.

A method for providing force output to a user of a force feedback device, said force feedback device being coupled to a host computer, the method comprising:

• determining a first force to be output by actuators of said force feedback device;
• outputting said first force at a first point in time occurring when a predetermined time interval has passed;
• determining a second force to be output by said actuators;
• if said predetermined time interval has not passed when said second force has been determined, waiting for a second point in time occurring when said predetermined time interval has passed after said first point in time, and outputting said second force at said second point in time;
• and
• if said predetermined time interval has passed when said second force has been determined, waiting for a successive point in time occurring when an integer number of said predetermined time intervals has passed after said first point in time, and outputting a third force at said successive point in time, said third force being appropriate to said successive point in time.