Methods and apparatus for controlling devices in a networked lighting system

• US 20030057886A1
• Filed: 05/30/2002
• Published: 03/27/2003
• Est. Priority Date: 08/26/1997
• Status: Active Grant

• Current Assignee: Philips Lighting North America Corporation (Signify N.V.)
• Original Assignee: Color Kinetics Incorporated (Signify N.V.)
• Inventors: Lys, Ihor A., Morgan, Frederick M.
• Granted Patent: US 6,777,891 B2
• Time in Patent Office: Days
• US Class Current: 315/291
• CPC Class Codes: F21S 4/10 with light sources attached to loose electric cables, e.g. Christmas tree lights
• CPC Class Codes: F21V 21/002 making direct electrical contact, e.g. by piercing F21V21/35 takes precedence
• CPC Class Codes: F21V 23/04 the elements being switches safety devices F21V25/00
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01R 4/24 Connections using contact members penetrating or cutting insulation or cable strands
• CPC Class Codes: H05B 47/155 Coordinated control of two or more light sources
• CPC Class Codes: H05B 47/18 via data-bus transmission

Abstract

Methods and apparatus for computer-based control of light sources in a networked lighting system. In one example, a plurality of LED-based lighting systems are arranged as computer controllable “light strings.” Applications contemplated for such light strings include, but are not limited to, decorative and entertainment-oriented lighting applications (e.g., Christmas tree lights, display lights, theme park lighting, video and other game arcade lighting, etc.). Via computer control, one or more such light strings may provide a variety of complex temporal and color-changing lighting effects. In one example, lighting data is communicated in a given light string in a serial manner, according to a variety of different data transmission and processing schemes. In another example, individual lighting systems of a light string are coupled together via a variety of different conduit configurations to provide for easy coupling and arrangement of multiple light sources constituting the light string. In yet another example, small LED-based lighting systems capable of being arranged in a light string configuration are manufactured as integrated circuits including data processing circuitry and control circuitry for LED light sources, and are packaged along with LEDs for convenient coupling to a conduit to connect multiple lighting systems.

Claims

1. A lighting system, comprising:

an LED lighting system adapted to receive a data stream through a first data port, generate at least one illumination condition based on at least a first portion of the data stream, and communicate at least a second portion of the data stream through a second data port; and

a housing adapted to retain the LED lighting system and electrically associate the first and second data ports with a data connection comprising an electrical conductor with at least one discontinuous section having a first side and a second side that is electrically isolated from the first side, the housing being adapted such that the first data port is electrically associated with the first side of the discontinuous section and the second data port is electrically associated with the second side of the discontinuous section.

2. The system of claim 1 wherein the housing further comprises a feature used to align the housing with data connection.

3. The system of claim 2 wherein the feature is adapted to align the housing with the at least one discontinuous section.

4. The system of claim 3 wherein the feature comprises a protrusion wherein the protrusion is inserted into the discontinuous section.

5. The system of claim 1 wherein at least one of the first data port and the second data port is electrically associated with the data connection through a insulation displacement connector.

6. The system of claim 1 wherein at least one of the first data port and the second data port is electrically associated with the data connection through a fastener.

7. The system of claim 1 wherein the electrical association of at least one of the first data port and the second data port also provides mechanical attachment;

wherein the mechanical attachment is sufficient to secure the housing to the data connection.

8. The system of claim 1 wherein the LED lighting system is adapted to strip the first portion from the data stream.

9. The system of claim 8 wherein the LED lighting system is further adapted to communicate at least an unstripped portion of the data stream to another system.

10. The system of claim 1 wherein the LED lighting system is adapted to manipulate the first portion of the data stream.

11. The system of claim 10 wherein the LED system is further adapted to communicate at least the manipulated first portion of the data stream.

12. The system of claim 11 wherein the LED system is further adapted to communicate at least an unmanipulated portion of the data stream.

13. The system of claim 1 wherein the LED lighting system is adapted to modify the first portion of the data stream.

14. The system of claim 13 wherein the LED lighting system is adapted to modify the first portion of the data stream by changing at least one bit of the first portion.

15. The system of claim 13 wherein the LED lighting system is adapted to modify the first portion of the data stream by adding at least one bit to the first portion.

16. The system of claim 13 wherein the first portion comprises a packet of data.

17. The system of claim 16 wherein the packet of data comprises the first unmodified packet of data received by the LED lighting system.

18. The system of claim 13 wherein the LED lighting system is adapted communicate at least the modified portion to another system.

19. The system of claim 1 wherein the LED lighting system is adapted to read a first portion of the data stream;

wherein the first portion comprises a data packet.

20. The system of claim 19 wherein the data packet comprises a first packet of data received through the data stream.

21. The system of claim 19 wherein the data packet comprises a first unmodified data packet received through the data stream.

22. The system of claim 19 wherein the data packet is associated with identification data.

23. The system of claim 22 wherein the identification data indicates the status of the data packet.

24. The system of claim 23 wherein the status indicates weather the data packet has been previously read by another system.

25. The system of claim 1 wherein the LED lighting system comprises a single color producing LED lighting system adapted to change the intensity of the color in response to the read portion of the data stream.

26. The system of claim 1 wherein the LED lighting system comprises a muli-color producing LED lighting system adapted to change at least one of an intensity and a color of the light produced by the LED lighting system in response to the first portion of the data stream.

27. The system of claim 26 wherein the LED lighting system controls LEDs through at least one of an analog control signal;

PWM control, and current control signal.

28. The system of claim 26 wherein the LED lighting system comprises at least two different color producing LEDs and the LED lighting system independently controls the at least two different color producing LEDs.

29. The system of claim 1 wherein the LED lighting system further comprises a platform wherein at least one LED and a processor are mounted on the platform;

and the housing retains the platform.

30. The system of claim 29 wherein the platform comprises a top side and a bottom side;

wherein the processor is associated with the bottom side and the at least one LED is associated with the top side.

31. The system of claim 30 wherein the at least one LED comprises a plurality of LEDs.

32. The system of claim 31 wherein the plurality of LEDs comprises at least two different color producing LEDs.

33. The system of claim 31 wherein the plurality of LEDs comprises red, green and blue producing LEDs.

34. The system of claim 30 wherein the platform has a top side surface area smaller than approximately 0.5 square inches.

35. The system of claim 30 wherein the platform has a top side surface area smaller than approximately 0.25 square inches.

36. The system of claim 30 wherein the platform has a top side surface area smaller than approximately 0.2 square inches.

37. The system of claim 30 wherein the platform has a top side surface area smaller than approximately 0.15 square inches.

38. The system of claim 30 wherein the platform has a top side surface area smaller than approximately 0.1 square inches.

39. The system of claim 30 wherein the platform has a top side surface area smaller than approximately 0.05 square inches.

40. The system of claim 1 further comprising an optic arranged in optical association with at least one LED of the LED lighting system.

41. The system of claim 40 wherein the at least one LED comprises a plurality of LEDs of at least two different colors;

wherein the optic is adapted to mix the light produced by the LEDs of at least two different colors.

42. The system of claim 40 wherein the optic comprises at least one of glass, plastic, and polycarbonate.

43. The system of claim 41 wherein the optic is at least one of transparent, translucent, partially transparent, partially translucent.

44. The system of claim 41 wherein the transmission of the optic is greater than approximately 10%.

45. The system of claim 41 wherein the transmission of the optic is greater than approximately 20%.

46. The system of claim 41 wherein the transmission of the optic is greater than approximately 30%.

47. The system of claim 41 wherein the transmission of the optic is greater than approximately 40%.

48. The system of claim 41 wherein the transmission of the optic is greater than approximately 50%.

49. The system of claim 41 wherein the transmission of the optic is greater than approximately 60%.

50. The system of claim 41 wherein the transmission of the optic is greater than approximately 70%.

51. The system of claim 41 wherein the transmission of the optic is greater than approximately 80%.

52. The system of claim 41 wherein the transmission of the optic is greater than approximately 90%.

53. The system of claim 41 wherein the transmission of the optic is approximately 100%.

54. The system of claim 40 wherein the optic is adapted to produce a prismatic effect.

55. A plurality of lighting systems of claim 1 wherein the data connection connects the plurality of lighting systems in series.

56. The plurality of lighting systems of claim 55 wherein the plurality is arranged on a surface.

57. The plurality of lighting systems of claim 56 wherein the surface comprises a buildings exterior surface.

58. The plurality of lighting systems of claim 56 wherein the surface comprises a buildings interior surface.

59. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged to illuminate a cove.

60. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged to illuminate a walkway.

61. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged to illuminate a pathway.

62. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged to illuminate a tree.

63. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged to illuminate a Christmas tree.

64. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged as a part of a game.

65. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged as part of a video game.

66. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged as part of a jukebox.

67. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged as part of a gambling machine.

68. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged as part of a slot machine.

69. The plurality of lighting systems of claim 55 wherein the plurality of lighting systems is arranged as part of a pinball machine.

70. An apparatus, comprising:

a data recognition circuit adapted to process at least a first portion of a data stream received by the apparatus;

an illumination control circuit coupled to the data recognition circuit and adapted to generate at least one illumination control signal in response to the processed first portion of the data stream; and

an output circuit adapted to transmit from the apparatus at least a second portion of the data stream.

71. The apparatus of claim 70 wherein the data recognition circuit is further adapted to strip at least the first portion of data from the data stream.

72. The apparatus of claim 71 wherein the second portion of the data stream comprises unstripped data.

73. The apparatus of claim 70 wherein the data recognition circuit is further adapted to modify the first portion of data such that the first portion is identified as being read.

74. The apparatus of claim 73 wherein the data recognition circuit is adapted to modify the first portion of data with an extra bit.

75. The apparatus of claim 73 wherein the data recognition circuit is adapted to modify at least one bit of the first portion of data.

76. The apparatus of claim 70 wherein the first portion of the data stream comprises a leading data packet of the data stream.

77. The apparatus of claim 76 wherein the leading data packet comprises an leading unmodified data packet of the data stream.

78. The apparatus of claim 70 wherein the at least one illumination control signal comprises at least one LED control signal.

79. The apparatus of claim 78 wherein the at least one LED control signal comprises at least one of a PWM signal, pulse amplitude modulated signal, analog control signal;

current control signal; and

voltage control signal.

80. The apparatus of claim 78 wherein the at least one LED control signal comprises a plurality of LED control signals.

81. The apparatus of claim 80 wherein the illumination control circuit is adapted to control a plurality of LEDs independently with the plurality of LED control signals.

82. The apparatus of claim 81 wherein the plurality of LEDs are adapted to produce at least two different colors.

83. The apparatus of claim 82 wherein the plurality of LEDs are adapted to produce red, green and blue light.

84. The apparatus of claim 70 wherein the illumination control signal comprises a non-LED control signal.

85. The apparatus of claim 70 further comprising a power management circuit wherein the power management circuit is adapted to receive power from a power source, control the power from the power source and deliver adequate power to at least one other circuit in the apparatus.

86. The apparatus of claim 85 wherein the power management circuit is adapted to deliver adequate power when the power source varies by less than approximately 10%.

87. The apparatus of claim 85 wherein the power management circuit is adapted to deliver adequate power when the power source varies by less than approximately 20%.

88. The apparatus of claim 85 wherein the power management circuit is adapted to deliver adequate power when the power source varies by less than approximately 30%.

89. The apparatus of claim 85 wherein the power management circuit is adapted to deliver adequate power when the power source varies by less than approximately 40%.

90. The apparatus of claim 85 wherein the power management circuit is adapted to deliver adequate power when the power source varies by less than approximately 50%.

91. The apparatus of claim 85 wherein the power management circuit is adapted to deliver adequate power when the power source varies by less than approximately 60%.

92. The apparatus of claim 85 wherein the power management circuit is adapted to deliver adequate power when the power source varies by less than approximately 70%.

93. The apparatus of claim 85 wherein the power management circuit is adapted to deliver adequate power when the power source varies by less than approximately 80%.

94. The apparatus of claim 85 wherein the power management circuit is adapted to deliver adequate power when the power source varies by less than approximately 90%.

95. The apparatus of claim 85 wherein the at least one other circuit comprises the illumination control circuit.

96. The apparatus of claim 95 wherein the adequate power delivered to the illumination control circuit provides for substantially regulated control of an illumination source.

97. The apparatus of claim 70, in combination with at least one other apparatus according to claim 70, wherein each apparatus of the combination is arranged to communicate in a serial fashion with another apparatus of the combination.

98. The combination of claim 97 wherein each apparatus is adapted to control at least one LED.

99. The combination of claim 98 wherein the at least one LED comprises a plurality of LEDs.

100. The combination of claim 99 wherein the plurality of LEDs comprises LEDs adapted to produce at least two different colors of light.

101. The combination of claim 100 wherein the at least two different colors of light comprise red, green and blue light.

102. The combination of claim 98 wherein each apparatus is associated with its own housing and the at least one LED is arranged in the housing.

103. The combination of claim 102 wherein for each apparatus, the housing is associated with an optic and at least one LED is optically associated with the optic.

104. The combination of claim 103 wherein the optic is adapted to diffuse light generated by the at least one LED.

105. The combination of claim 103 wherein the optics is adapted to transmit light generated by the at least one LED.

106. The apparatus of claim 70 wherein the apparatus is formed as an integrated circuit mounted on a platform, and wherein at least one LED is mounted on the platform.

107. The integrated circuit of claim 106 wherein the platform comprises a first side and a second side, wherein the integrated circuit is mounted on the first side and the at least one LED is mounted on the second side.

108. The integrated circuit of claim 107 wherein the at least one LED comprises a plurality of LEDs.

109. The integrated circuit of claim 108 wherein the illumination control circuit is adapted to independently control the plurality of LEDs.

110. A method of controlling a plurality of lighting systems, comprising acts of:

communicating a data stream to a first lighting system of the plurality of lighting systems;

receiving the data stream at the first lighting system and reading at least a first portion of the data stream;

generating at least one lighting effect at the first lighting system in response to the first portion of the data stream; and

communicating at least a second portion of the data stream to a second lighting system of the plurality of lighting systems.

111. The method of claim 110 wherein the plurality of lighting systems comprise a plurality of LED lighting systems.

112. The method of claim 110 wherein the plurality of lighting systems comprise a plurality of illumination systems.

113. The method of claim 110 wherein the plurality of lighting systems comprise a plurality of non-LED lighting systems.

114. The method of claim 110 wherein the plurality of lighting systems comprise a plurality of color changing LED lighting systems.

115. The method of claim 110, further comprising the step of:

causing the first lighting system to strip the first portion of the data stream from the data stream; and

wherein the step of causing the first lighting system to communicate at least a second portion of the data stream to second lighting system of the plurality of lighting systems comprises causing the first lighting system to communicate at least a second portion of the data stream to second lighting system of the plurality of lighting systems;

wherein the second portion of the data stream does not include the first portion.

116. The method of claim 110, further comprising the step of:

causing the first lighting system to modify the first portion of the data stream such that the remaining lighting systems in the plurality of lighting systems recognize the first portion has been read by the first lighting system; and

wherein the step of causing the first lighting system to communicate at least a second portion of the data stream to another of the plurality of lighting systems comprises causing the first lighting system to communicate at least a second portion of the data stream to another of the plurality of lighting systems;

wherein the second portion of the data stream includes the modified first portion of the data stream.

117. The method of claim 116 wherein the step of causing the first lighting system to modify the first portion of the data stream such that the remaining lighting systems in the plurality of lighting systems recognize the first portion has been read by the first lighting system comprises causing the first lighting system to modify the first portion of the data stream with an extra bit such that the remaining lighting systems in the plurality of lighting systems recognize the first portion has been read by the first lighting system.

118. The method of claim 116 wherein the step of causing the first lighting system to modify the first portion of the data stream such that the remaining lighting systems in the plurality of lighting systems recognize the first portion has been read by the first lighting system comprises causing the first lighting system to modify a bit of the first portion of the data stream such that the remaining lighting systems in the plurality of lighting systems recognize the first portion has been read by the first lighting system.

119. The method of claim 110 wherein the data stream comprises a plurality of data packets;

wherein the step of causing the first lighting system to receive the data stream and to read a first portion of the data stream comprises causing the first lighting system to receive the data stream and to read a first unread data packet from the data stream; and

wherein the step of causing the first lighting system to generate a lighting effect in response to the first portion of the data stream comprises causing the first lighting system to generate a lighting effect in response to the first unread data packet from the data stream.

120. An integrated circuit to control at least one illumination source, comprising:

a data reception circuit;

an illumination control signal generation circuit coupled to the data reception circuit; and

a clock generating circuit coupled to the data reception circuit,

wherein;

the data reception circuit is adapted to extract information from serial data input to the integrated circuit in coordination with a clock pulse generated by the clock generating circuit; and

the illumination control signal generation circuit is adapted to generate at least one illumination control signal to control the at least one illumination source based on the extracted information.

121. The integrated circuit of claim 120, wherein the clock generating circuit comprises a non-precision frequency reference.

122. The integrated circuit of claim 121 wherein the non-precision frequency reference produces the clock pulse at greater than approximately four times the rate of a desired data read rate.

123. The integrated circuit of claim 120, wherein the illumination signal generation circuit produces at least one switchable constant current control signal.

124. The integrated circuit of claim 123, wherein the at least one switchable constant current control signal is arranged to operate at least one LED without any external components.

125. The integrated circuit of claim 124, wherein the at least one LED comprises a plurality of LEDs.

126. The integrated circuit of claim 125, wherein the at least one switchable constant current control signal comprises a plurality of controllable switchable constant current control signals and each of the plurality of controllable switchable constant current signals is arranged to independently control at least one separate LED of the plurality of LEDs without any external components.

127. The integrated circuit of claim 120, wherein a transmission circuit uses a first edge of a serial data signal to communicate the first edge through a transmission port.

128. The integrated circuit of claim 127, wherein a second edge of the serial data signal to coordinate the transmission of a subsequent second edge of data through a data transmission circuit.

129. The integrated circuit of claim 127, wherein a second edge of data is transmitted through the transmission port at a time based on a desired data state.

130. The integrated circuit of claim 120, further comprising:

a voltage reference circuit;

wherein the voltage reference circuit is adapted to regulate current delivered from the illumination control generation circuit.

131. The integrated circuit of claim 130, wherein the voltage reference circuit senses the voltage value of an external component to regulate the current delivered from the illumination control generation circuit.

132. The integrated circuit of claim 131, wherein the illumination control generation circuit generates at least one switchable constant current control signal.

133. The integrated circuit of claim 131, wherein the external component comprises a resistor.

134. An integrated circuit, adapted to read serial data input to the integrated circuit so as to directly control at least one LED, wherein the integrated circuit is adapted to read the serial data without the aid of an external frequency reference.

135. The integrated circuit of claim 134 wherein the at least one LED comprises a plurality of LEDs.

136. The integrated circuit of claim 135 wherein the integrated circuit is adapted to independently control each of the plurality of LEDs.

137. An integrated circuit, comprising:

a data reception circuit;

a data transmission circuit;

an illumination control signal generation circuit; and

a voltage reference circuit,

wherein the voltage reference circuit is adapted to regulate current provided by the illumination control generation circuit.

138. The integrated circuit of claim 137, wherein the voltage reference circuit senses a voltage value of an external component to regulate the current delivered from the illumination control generation circuit.

139. The integrated circuit of claim 138 wherein the external component is a resistor.

140. The integrated circuit of claim 139, wherein the illumination control generation circuit generates at least one switchable constant current control signal.

141. An apparatus adapted to process serial data and to control at least one LED in response to the serial data, comprising:

a counter circuit adapted to measure a first period between a first edge of a first polarity of the serial data and a second edge of the first polarity of the serial data, the counter circuit being further adapted to measure a second period between the first edge of the first polarity of the serial data and a first edge of a second polarity of the serial data, the counter circuit being further adapted to compare the second period with a predetermined fraction of the first period to determine if the serial data is in a first state.

142. The apparatus of claim 141 wherein the first polarity comprises a rising edge of the serial data and the second polarity comprises a falling edge of the serial data.

143. The apparatus of claim 141 wherein the first polarity comprises a falling edge of the serial data and the second polarity comprises a rising edge of the serial data.

144. The apparatus of claim 141 wherein the predetermined fraction is approximately one half.

145. The apparatus of claim 144 wherein the counter circuit is adapted to determine that the serial data is in the first data state when the second period is less than approximately one half of the first period.

146. The apparatus of claim 145 wherein the first state comprises a high data signal.

147. The apparatus of claim 145 wherein the first state comprises a low data signal.

148. The apparatus of claim 141 wherein the counter circuit is adapted to detect the location of a second edge of the second polarity by sampling a state of the serial data at a predetermined sampling period determined from the first period.

149. The apparatus of claim 148 wherein the predetermined sampling period is approximately half of the first period.

150. The apparatus of claim 148 wherein the predetermined sampling period is less than half of the first period.

151. The apparatus of claim 141, further comprising:

a transmitting circuit adapted to asynchronously pass the first edge of the first polarity of the serial data from an input port to an output port and transmit the first edge of the second polarity to an output port at a time based on a desired data state to be transmitted.

152. The apparatus of claim 151 wherein the time is calculated from the second period.

153. The apparatus of claim 151 wherein the time is approximately the same as the second period.

154. The apparatus of claim 151 wherein the time is determined from one of at least two trigger values based on the desired data state to be transmitted.

155. The apparatus of claim 154 wherein the at least two trigger values comprise a first value equal to less than half the first period and a second value equal to more than half the first period.

156. The apparatus of claim 154 wherein the at least two trigger values comprise approximately one forth of the first period and approximately three fourths of the first period.

157. The apparatus of claim 154 wherein the at least one of the at least two trigger values comprises a fixed value.

158. The apparatus of claim 154 wherein the at least one of the at least two trigger values comprises a value calculated by subtracting a fixed value from the first period.

159. The apparatus of claim 154 wherein the at least one of the at least two trigger values comprises a value calculated by subtracting a variable value from the first period, wherein the variable value is calculated from the first period.

160. An integrated circuit adapted to read serial data and to control at least one LED in response to the serial data, comprising:

a counter circuit adapted to measure a number of data transitions of the serial data within a predetermined period and determine if the data transitions represent a first data state.

161. The integrated circuit of claim 160 wherein the at least one LED comprises a plurality of LEDs.

162. The integrated circuit of claim 161 wherein the integrated circuit is adapted to independently control the plurality of LEDs.

163. An integrated circuit, comprising:

a power input pin adapted to receive external power;

a ground pin adapted to connect the integrated circuit to a common reference potential;

a reference pin adapted to connect to an external component to provide the integrated circuit a reference from which to regulate at least one LED;

a serial data input pin for receiving serial data;

a serial data output pin for transmitting serial data; and

at least one switchable constant current output pin adapted to control the at least one LED.

164. The integrated circuit of claim 163 wherein the at least one LED comprises at least three LEDs and the at least one switchable constant current output pin comprises three switchable constant current output pins adapted to independently control separate LEDs of the at least three LEDs.

165. The integrated circuit of claim 164 wherein the total number of functional pins equals eight.

166. The integrated circuit of claim 163, further comprising:

an internal clock generation circuit wherein the internal clock generation circuit generates a clock pulse and the integrated circuit is further adapted to read serial data in coordination with the clock pulse.

167. The integrated circuit of claim 163 wherein the integrated circuit does not require a precision external clock signal to properly read serial data.

168. A method of processing serial data to control at least one LED in response to the serial data, comprising acts of:

(A) measuring a number of data transitions of the serial data within a predetermined period; and

(B) determining if the data transitions represent a first data state based on the act (A).

169. The method of claim 168, wherein the act (A) comprises acts of:

measuring a first period between a first edge of a first polarity of the serial data and a second edge of the first polarity of the serial data; and

measuring a second period between the first edge of the first polarity of the serial data and a first edge of a second polarity of the serial data.

170. The method of claim 169, wherein the act (B) comprises an act of:

(B1) comparing the second period with a predetermined fraction of the first period to determine if the serial data is in the first data state.

171. The method of claim 170, wherein the first polarity comprises a rising edge of the serial data and the second polarity comprises a falling edge of the serial data.

172. The method of claim 170, wherein the first polarity comprises a falling edge of the serial data and the second polarity comprises a rising edge of the serial data.

173. The method of claim 170, wherein the predetermined fraction is approximately one half.

174. The method of claim 170, wherein the act (B1) includes an act of:

determining that the serial data is in the first data state when the second period is less than approximately one half of the first period.

175. The method of claim 170, wherein the first state comprises a high data signal.

176. The method of claim 170, wherein the first state comprises a low data signal.

177. The method of claim 170, further comprising an act of:

detecting a location of a second edge of the second polarity by sampling a state of the serial data at a predetermined sampling period determined from the first period.

178. The method of claim 177, wherein the predetermined sampling period is approximately half of the first period.

179. The method of claim 177, wherein the predetermined sampling period is less than half of the first period.

180. The method of claim 170, further comprising acts of:

asynchronously passing the first edge of the first polarity of the serial data from an input port to an output port; and

transmitting the first edge of the second polarity to the output port at a time based on a desired data state to be transmitted.

181. The method of claim 180, further comprising an act of calculating the time from the second period.

182. The method of claim 181, wherein the time is approximately the same as the second period.

183. The method of claim 180, further comprising an act of:

determining the time from one of at least two trigger values based on the desired data state to be transmitted.

184. The method of claim 183, wherein the at least two trigger values comprise a first value equal to less than half the first period and a second value equal to more than half the first period.

185. The method of claim 183, wherein the at least two trigger values comprise approximately one forth of the first period and approximately three fourths of the first period.

186. The method of claim 183, wherein the at least one of the at least two trigger values comprises a fixed value.

187. The method of claim 183, further comprising an act of:

calculating at least one of the at least two trigger values by subtracting a fixed value from the first period.

188. The method of claim 183, further comprising an act of:

calculating at least one of the at least two trigger values by subtracting a variable value from the first period, wherein the variable value is calculated from the first period.