Bit encoding system and method

• US 6,574,284 B1
• Filed: 02/02/2000
• Issued: 06/03/2003
• Est. Priority Date: 03/20/1999
• Status: Expired due to Term

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Jordan, Mark John
• Primary Examiner(s): Vo, Don N.
• Assistant Examiner(s): GHULAMALI, QUTBUDDIN
• Application Number:
  US09/496,325
• Time in Patent Office: 1,217 Days
• Field of Search: 375/257, 375/268, 375/269, 375/300, 375/320, 375/356, 375/357, 370/503, 370/514, 332/149, 332/141
• US Class Current: 375/268
• CPC Class Codes: H04L 2007/047 using a sine signal or unmodulated carrier
• CPC Class Codes: H04L 27/02 Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation H04L27/32 takes precedence
• CPC Class Codes: H04L 7/0008 Synchronisation information channels, e.g. clock distribution lines

Abstract

A bit encoding system for use with a bus (7) of a distributed microcontroller network (200,300), includes a waveform generator (100) for generating a substantially sinusoidal waveform. A modulation arrangement (340, 341) is arranged to amplitude modulate the waveform between first and second amplitudes to define first and second data values. A zero crossing point of the waveform is used to define timing information for the bus (7).

Claims

1. A bit encoding system for use with a bus of a distributed microcontroller network, comprising means for providing a first substantially sinusoidal waveform which is amplitude modulated between first and second amplitudes to define first and second data values, and means for selectively switching between the first and second data values substantially at the occurrence of a predetermined periodic parameter for defining timing information for the bus.

2. The system of claim 1 wherein the predetermined periodic parameter is a zero crossing point of the first sinusoidal waveform.

3. The system of claim 2 wherein the predetermined periodic parameter is the negative to positive zero crossing point of the sinusoidal waveform.

4. A bit encoding system for use with a first and a second bus of a distributed microcontroller network, comprising means for providing a first substantially sinusoidal waveform which is amplitude modulated between first and second amplitudes to define first and second data values for the first bus, and which has a predetermined periodic parameter for defining timing information for the first bus, and means for providing a second substantially sinusoidal waveform for the second bus, the second waveform being amplitude modulated in antiphase to the fist waveform, and having a predetermined periodic parameter for defining timing information for the second bus.

5. The system of claim 4 wherein the predetermined periodic parameter of the second waveform is phase shifted by a half wavelength from the predetermined periodic parameter of the first waveform.

6. A method for bit encoding a bus of a distributed microcontroller network, the method comprising:

amplitude modulating a first substantially sinusoidal waveform between first and second amplitudes to define first and second data values; and

,

selectively switching between the first and second data values substantially at the occurrence of a predetermined periodic parameter for defining timing information for the bus.

7. The method of claim 6 wherein the predetermined periodic parameter is a zero crossing point of the first sinusoidal waveform.

8. The method of claim 7 wherein the predetermined periodic parameter is the negative to positive zero crossing point of the sinusoidal waveform.

9. The method of claim 6 comprising provising a second substantially sinusoidal waveform for a second bus, the further waveform being amplitude modulated in antiphase to the first waveform, and having a predetermined periodic parameter for defining timing information for the second bus.

10. The method of claim 9 wherein the predetermined periodic parameter of the second waveform is phase shifted by a half wavelength from the predetermined periodic parameter of the first waveform.