Author: claimsbot

1. A data compression system comprising:
a first plurality of compression engines, wherein each of the first plurality of compression engines implements a different respective data compression algorithm, wherein at least one of the first plurality of compression engines implements a parallel data compression algorithm, and wherein each of the first plurality of compression engines is configured to:
receive uncompressed data; and
compress the uncompressed data using its respective data compression algorithm;

wherein the first plurality of compression engines produce a plurality of different versions of the compressed data;
decision logic coupled to the first plurality of compression engines and configured to:
select one of the plurality of different versions of the compressed data based upon one or more predetermined metrics; and
output the selected compressed data.
2. The data compression system of claim 1, wherein the at least one of the first plurality of compression engines implements a parallel lossless data compression algorithm.
3. The data compression system of claim 1, wherein the at least one of the first plurality of compression engines implements a parallel dictionary-based data compression algorithm.
4. The data compression system of claim 1, wherein the at least one of the first plurality of compression engines implements a parallel statistical data compression algorithm.
5. The data compression system of claim 1, wherein the at least one of the first plurality of compression engines implements a parallel data compression algorithm based on a Lempel-Ziv (LZ) algorithm.
6. The data compression system of claim 1, wherein the uncompressed data comprises a plurality of symbols, wherein the at least one of the first plurality of compression engines is operable to compare each of a plurality of received symbols with each of a plurality of entries in a history table concurrently.
7. The data compression system of claim 1,
wherein the at least one of the first plurality of compression engines comprises:
an input for receiving the uncompressed data, wherein the uncompressed data comprises a plurality of symbols, wherein the plurality of symbols includes a first symbol, a last symbol, and one or more middle symbols;
a history table comprising entries, wherein each entry comprises at least one symbol;
a plurality of comparators for comparing the plurality of symbols with entries in the history table, wherein the plurality of comparators are operable to compare each of the plurality of symbols with each entry in the history table concurrently, wherein the plurality of comparators produce compare results;
match information logic coupled to the plurality of comparators for determining match information for each of the plurality of symbols based on the compare results, wherein the match information logic is operable to determine if a contiguous match occurs for one or more of the one or more middle symbols that does not involve a match with either the first symbol or the last symbol; and
an output coupled to the match information logic for outputting compressed data in response to the match information.
8. The data compression system of claim 1, wherein each of the first plurality of compression engines implements a parallel data compression algorithm.
9. The data compression system of claim 8,
wherein each of the first plurality of compression engines implements a parallel dictionary-based data compression algorithm.
10. The data compression system of claim 9,
wherein a first compression engine implements a parallel dictionary-based data compression algorithm using tag based encoding;
wherein a second compression engine implements a parallel dictionary-based data compression algorithm using escape characters to differentiate between compressed and raw data sequences in the compressed data.
11. The data compression system of claim 8,
wherein each of the first plurality of compression engines comprises:
an input for receiving the uncompressed data, wherein the uncompressed data comprises a plurality of symbols, wherein the plurality of symbols includes a first symbol, a last symbol, and one or more middle symbols;
a history table comprising entries, wherein each entry comprises at least one symbol;
a plurality of comparators for comparing the plurality of symbols with entries in the history table, wherein the plurality of comparators are operable to compare each of the plurality of symbols with each entry in the history table concurrently, wherein the plurality of comparators produce compare results;
match information logic coupled to the plurality of comparators for determining match information for each of the plurality of symbols based on the compare results, wherein the match information logic is operable to determine if a contiguous match occurs for one or more of the one or more middle symbols that does not involve a match with either the first symbol or the last symbol; and
an output coupled to the match information logic for outputting compressed data in response to the match information.
12. The data compression system of claim 1,
wherein the one or more predetermined metrics includes compression ratio.
13. The data compression system of claim 1,
wherein the one or more predetermined metrics includes compression speed.
14. The data compression system of claim 1, wherein, in selecting one of the plurality of different versions of the compressed data, the decision logic is further configured to select a version of the compressed data with a highest compression ratio from among the plurality of versions of the compressed data.
15. The data compression system of claim 1, wherein the decision logic is further configured to:
determine a particular data compression algorithm used in the compression of the selected compressed data; and
output information indicating the particular data compression algorithm used in the compression of the selected compressed data.
16. The data compression system of claim 15, wherein the decision logic is further configured to:
encode the information indicating the particular data compression algorithm used in the compression of the selected compressed data into the selected compressed data.
17. The data compression system of claim 1, wherein a first compression engine of the first plurality of compression engines comprises a second plurality of compression engines, wherein each of the second plurality of compression engines implements a first data compression algorithm;
wherein the second plurality of compression engines are configured to compress a plurality of portions of the uncompressed data using the first data compression algorithm to produce a plurality of compressed portions of the uncompressed data; and
wherein the first compression engine of the first plurality of compression engines is configured to merge the plurality of compressed portions of the uncompressed data to produce a version of the compressed data.
18. The data compression system of claim 17, wherein the second plurality of compression engines is configured to compress the plurality of portions of the uncompressed data in a parallel fashion.
19. A data compression system comprising:
a plurality of compression engines, wherein each of the plurality of compression engines implements a different data compression algorithm, wherein at least one of the plurality of compression engines implements a parallel lossless data compression algorithm;
and wherein the plurality of compression engines are configured to:
receive uncompressed data; and
compress the uncompressed data using the different data compression algorithms to produce a plurality of different versions of the compressed data;

decision logic coupled to the plurality of compression engines and configured to:
select one of the plurality of different versions of the compressed data as a most qualified version of the compressed data based upon one or more predetermined metrics; and
output the most qualified version of the compressed data.
20. The data compression system of claim 19, wherein the at least one of the plurality of compression engines implements a parallel dictionary-based data compression algorithm.
21. The data compression system of claim 20, wherein the uncompressed data comprises a plurality of symbols, wherein the at least one of the plurality of compression engines is operable to compare each of a plurality of received symbols with each of a plurality of entries in a history table concurrently.
22. The data compression system of claim 19,
wherein the at least one of the plurality of compression engines comprises:
an input for receiving the uncompressed data, wherein the uncompressed data comprises a plurality of symbols, wherein the plurality of symbols includes a first symbol, a last symbol, and one or more middle symbols;
a history table comprising entries, wherein each entry comprises at least one symbol;
a plurality of comparators for comparing the plurality of symbols with entries in the history table, wherein the plurality of comparators are operable to compare each of the plurality of symbols with each entry in the history table concurrently, wherein the plurality of comparators produce compare results;
match information logic coupled to the plurality of comparators for determining match information for each of the plurality of symbols based on the compare results, wherein the match information logic is operable to determine if a contiguous match occurs for one or more of the one or more middle symbols that does not involve a match with either the first symbol or the last symbol; and
an output coupled to the match information logic for outputting compressed data in response to the match information.
23. The data compression system of claim 19, wherein at least one of the plurality of compression engines performs parallel data compression using a plurality of parallel compression engines each operating in parallel on a different respective portion of said uncompressed data.
24. A data compression system comprising:
a plurality of compression engines, wherein each of the plurality of compression engines implements a different data compression algorithm, wherein at least one of the plurality of compression engines implements a parallel lossless data compression algorithm;
first logic coupled to the plurality of compression engines and configured to:
receive uncompressed data;
send the uncompressed data to each of the plurality of compression engines;

wherein each of the plurality of compression engines is configured to:
receive the uncompressed data from the first logic;
compress the uncompressed data using a data compression algorithm implemented by the particular compression engine to produce a version of compressed data; and
output the compressed data;

second logic coupled to the plurality of compression engines and configured to:
receive from the plurality of compression engines a plurality of different versions of the compressed data each compressed with a different compression algorithm; and
select one of the plurality of different versions of the compressed data based upon one or more predetermined metrics; and
output the selected compressed data.
25. The data compression system of claim 24, wherein the at least one of the plurality of compression engines implements a parallel dictionary-based data compression algorithm.
26. The data compression system of claim 25, wherein the uncompressed data comprises a plurality of symbols, wherein the at least one of the plurality of compression engines is operable to compare each of a plurality of received symbols with each of a plurality of entries in a history table concurrently.
27. The data compression system of claim 24,
wherein the at least one of the plurality of compression engines comprises:
an input for receiving the uncompressed data, wherein the uncompressed data comprises a plurality of symbols, wherein the plurality of symbols includes a first symbol, a last symbol, and one or more middle symbols;
a history table comprising entries, wherein each entry comprises at least one symbol;
a plurality of comparators for comparing the plurality of symbols with entries in the history table, wherein the plurality of comparators are operable to compare each of the plurality of symbols with each entry in the history table concurrently, wherein the plurality of comparators produce compare results;
match information logic coupled to the plurality of comparators for determining match information for each of the plurality of symbols based on the compare results, wherein the match information logic is operable to determine if a contiguous match occurs for one or more of the one or more middle symbols that does not involve a match with either the first symbol or the last symbol; and
an output coupled to the match information logic for outputting compressed data in response to the match information.
28. The data compression system of claim 24,
wherein the one or more predetermined metrics includes compression ratio.
29. The data compression system of claim 24,
wherein the one or more predetermined metrics includes compression speed.
30. The data compression system of claim 24, wherein, in selecting the compressed data, the second logic is further configured to select a version of the compressed data with a highest compression ratio from among the plurality of different versions of the compressed data.
31. The data compression system of claim 24, wherein the second logic is further configured to:
determine a particular data compression algorithm used in the compression of the selected compressed data; and
output information indicating the particular data compression algorithm used in the compression of the selected compressed data.
32. A system comprising:
a processor;
a memory coupled to the processor and operable to store data for use by the processor;
data compression logic coupled to the memory, comprising:
a plurality of compression engines, wherein each of the plurality of compression engines implements a different respective data compression algorithm, wherein at least one of the plurality of compression engines implements a parallel data compression algorithm, and wherein each of the plurality of compression engines is configured to:
receive uncompressed data; and
compress the uncompressed data using its respective data compression algorithm;

wherein the plurality of compression engines produce a plurality of different versions of the compressed data;
decision logic coupled to the plurality of compression engines and configured to:
select one of the plurality of different versions of the compressed data based upon one or more predetermined metrics; and
output the selected compressed data.
33. The system of claim 32, wherein the at least one of the plurality of compression engines implements a parallel dictionary-based data compression algorithm.
34. The system of claim 33, wherein the uncompressed data comprises a plurality of symbols, wherein the at least one of the plurality of compression engines is operable to compare each of a plurality of received symbols with each of a plurality of entries in a history table concurrently.
35. The system of claim 32,
wherein the at least one of the plurality of compression engines comprises:
an input for receiving the uncompressed data, wherein the uncompressed data comprises a plurality of symbols, wherein the plurality of symbols includes a first symbol, a last symbol, and one or more middle symbols;
a history table comprising entries, wherein each entry comprises at least one symbol;
a plurality of comparators for comparing the plurality of symbols with entries in the history table, wherein the plurality of comparators are operable to compare each of the plurality of symbols with each entry in the history table concurrently, wherein the plurality of comparators produce compare results;
match information logic coupled to the plurality of comparators for determining match information for each of the plurality of symbols based on the compare results, wherein the match information logic is operable to determine if a contiguous match occurs for one or more of the one or more middle symbols that does not involve a match with either the first symbol or the last symbol; and
an output coupled to the match information logic for outputting compressed data in response to the match information.
36. The system of claim 32,
wherein each of the plurality of compression engines implements a parallel dictionary-based data compression algorithm.
37. The system of claim 36,
wherein a first compression engine implements a parallel dictionary-based data compression algorithm using tag based encoding;
wherein a second compression engine implements a parallel dictionary-based data compression algorithm using escape characters to differentiate between compressed and raw data sequences in the compressed data.
38. The system of claim 32, wherein the decision logic is further configured to:
determine a particular data compression algorithm used in the compression of the selected compressed data; and
output information indicating the particular data compression algorithm used in the compression of the selected compressed data.
39. The system of claim 32, wherein the data compression logic is configured to write the selected compressed data to the memory.
40. The system of claim 32, wherein the system further comprises:
a plurality of decompression engines, wherein the plurality of decompression engines implement decompression algorithms corresponding to the different respective data compression algorithms of the plurality of compression engines;
decompression logic coupled to the plurality of decompression engines and configured to:
determine a first decompression engine of the plurality of decompression engines that implements a particular data compression algorithm used in compression of first compressed data; and
provide the first compressed data to the first decompression engine;

wherein the first decompression engine is configured to decompress the first compressed data to produce the uncompressed data.
41. The system of claim 40, wherein the data compression logic is further configured to write data compression information indicating the particular data compression algorithm used in the compression of the first compressed data to the memory;
wherein, in said determining the first decompression engine, the decompression logic is further configured to read the data compression information to determine the particular data compression algorithm.
42. The system of claim 32, further comprising:
a memory controller coupled to the processor and the memory and configured to control the memory, wherein the data compression logic is comprised in the memory controller.
43. The system of claim 32, wherein the data compression logic is comprised in the processor.
44. The system of claim 32, further comprising:
wherein the memory comprises one or more memory modules, wherein the data compression logic is comprised in one of the one or more memory modules.
45. The system of claim 32, further comprising a network interface device operable to interface the system to a network, wherein the data compression logic is comprised in the network interface device.
46. A method for compressing data in a system comprising a memory, the method comprising:
receiving uncompressed data;
providing the uncompressed data to a plurality of compression engines, wherein each of the plurality of compression engines implements a different respective data compression algorithm;
the plurality of compression engines compressing the uncompressed data using the different respective data compression algorithms, thereby producing a plurality of different versions of the compressed data, wherein said compressing comprises at least one of the plurality of compression engines compressing the uncompressed data using a parallel lossless data compression algorithm; and
selecting one of the plurality of different versions of the compressed data based upon one or more predetermined metrics.
47. The method of claim 46, further comprising:
outputting the selected compressed data.
48. The method of claim 46, wherein the at least one of the plurality of compression engines implements a parallel statistical data compression algorithm;
wherein the plurality of compression engines compressing the uncompressed data includes the at least one of the plurality of compression engines compressing the uncompressed data using the parallel statistical data compression algorithm.
49. The method of claim 46, wherein the at least one of the plurality of compression engines implements a parallel dictionary-based data compression algorithm;
wherein the plurality of compression engines compressing the uncompressed data includes the at least one of the plurality of compression engines compressing the uncompressed data using the parallel dictionary-based data compression algorithm.
50. The method of claim 49,
wherein the uncompressed data comprises a plurality of symbols;
wherein the at least one of the plurality of compression engines compressing the data using the parallel dictionary-based data compression algorithm comprises the at least one of the plurality of compression engines comparing each of a plurality of received symbols with each of a plurality of entries in a history table concurrently.
51. The method of claim 50,
wherein the at least one of the plurality of compression engines compressing the uncompressed data using the parallel dictionary-based data compression algorithm comprises:
receiving the uncompressed data, wherein the uncompressed data comprises a plurality of symbols, wherein the plurality of symbols includes a first symbol, a last symbol, and one or more middle symbols;
maintaining a history table comprising entries, wherein each entry comprises at least one symbol;
comparing the plurality of symbols with entries in the history table in a parallel fashion, wherein said comparing in a parallel fashion comprises comparing each of the plurality of symbols with each entry in the history table concurrently, wherein said comparing produces compare results;
determining match information for each of the plurality of symbols based on the compare results, wherein said determining match information includes determining if a contiguous match occurs for one or more of the one or more middle symbols that does not involve a match with either the first symbol or the last symbol; and
outputting compressed data in response to the match information.
52. The method of claim 46, wherein each of the plurality of compression engines implements a different parallel dictionary-based data compression algorithm;
wherein the plurality of compression engines compressing the uncompressed data includes the plurality of compression engines compressing the uncompressed data using the different parallel dictionary-based data compression algorithms.
53. The method of claim 52,
wherein the plurality of compression engines compressing the uncompressed data includes:
a first compression engine compressing the uncompressed data using a parallel dictionary-based data compression algorithm using tag based encoding; and
a second compression engine compressing the uncompressed data using a parallel dictionary-based data compression algorithm using escape characters to differentiate between compressed and raw data sequences.
54. The method of claim 46,
wherein the one or more predetermined metrics includes compression ratio.
55. The method of claim 46,
wherein the one or more predetermined metrics includes compression speed.
56. The method of claim 46, further comprising writing the selected compressed data to the memory.
57. The method of claim 46, further comprising:
incorporating data compression information into the selected compressed data, wherein the data compression information indicates a particular data compression algorithm used in the compression of the selected compressed data.
58. The method of claim 57, further comprising:
determining that the selected compressed data needs to be decompressed;
receiving the selected compressed data;
examining the data compression information to determine the particular data compression algorithm used in compressing the selected compressed data;
selecting a decompression engine from a plurality of decompression engines, wherein the selected decompression engine implements a decompression algorithm for decompressing data compressed using the particular data compression algorithm;
providing the selected compressed data to the selected decompression engine; and
the selected decompression engine decompressing the selected compressed data using the decompression algorithm to produce the uncompressed data.
59. A method for compressing data in a system comprising a memory, the method comprising:
receiving uncompressed data;
providing the uncompressed data to a plurality of compression engines, wherein each of the plurality of compression engines implements a different data compression algorithm;
the plurality of compression engines compressing the uncompressed data using a plurality of different data compression algorithms to produce a plurality of different versions of the compressed data, wherein said compressing includes at least one of the plurality of compression engines compressing the uncompressed data using a parallel lossless dictionary-based data compression algorithm; and
selecting one of the plurality of different versions of the compressed data as a most qualified version of the compressed data based upon one or more predetermined metrics.
60. The method of claim 59, wherein selecting the most qualified version of the compressed data further comprises selecting a version of the compressed data with a highest compression ratio from among the plurality of different versions of the compressed data.
61. The method of claim 59, wherein at least one of the first plurality of compression engines implements a parallel data compression algorithm based on a serial statistical data compression algorithm.
62. The method of claim 59, wherein at least one of the first plurality of compression engines implements a parallel data compression algorithm based on a Lempel-Ziv (LZ) algorithm.
63. The method of claim 59, wherein a first of the first plurality of compression engines comprises a second plurality of compression engines, wherein each of the second plurality of compression engines implements a first data compression algorithm, wherein said compressing further comprises:
providing a different portion of the uncompressed data to each of the second plurality of compression engines;
each of the second plurality of compression engines compressing the different portion of the uncompressed data using the first data compression algorithm to produce a compressed portion of the uncompressed data;
wherein the second plurality of compression engines compress a plurality of different portions of the uncompressed data to produce a plurality of compressed portions of the uncompressed data; and
merging the plurality of compressed portions of the uncompressed data to produce a version of the compressed data.
64. The method of claim 63, wherein the second plurality of compression engines is configured to compress the plurality of portions of the uncompressed data in a parallel fashion.
65. The data compression system of claim 63, wherein the first data compression algorithm is a parallel dictionary-based data compression algorithm.
66. The method of claim 59, wherein at least one of the plurality of compression engines performs parallel data compression using a plurality of parallel compression engines each operating in parallel on a different respective portion of said uncompressed data.
67. A data compression system comprising:
a plurality of compression engines, wherein each of the plurality of compression engines implements a different respective parallel dictionary-based data compression algorithm, and wherein each of the plurality of compression engines is configured to:
receive uncompressed data, wherein the uncompressed data comprises a plurality of symbols; and
compress the uncompressed data using its respective data compression algorithm, wherein each of the plurality of compression engines is operable to compare each of a plurality of received symbols with each of a plurality of entries in a history table concurrently;

wherein the plurality of compression engines produce a plurality of different versions of the compressed data;
decision logic coupled to the plurality of compression engines and configured to:
select one of the plurality of different versions of the compressed data based upon one or more predetermined metrics; and
output the selected compressed data.
68. The data compression system of claim 67,
wherein a first compression engine implements a parallel dictionary-based data compression algorithm using tag based encoding;
wherein a second compression engine implements a parallel dictionary-based data compression algorithm using escape characters to differentiate between compressed and raw data sequences in the compressed data.
69. The data compression system of claim 67,
wherein the plurality of compression engines share a common history table.
70. The data compression system of claim 67,
wherein each of the plurality of compression engines includes its own history table.
71. The data compression system of claim 67,
wherein each of the first plurality of compression engines comprises:
an input for receiving the uncompressed data, wherein the uncompressed data comprises a plurality of symbols, wherein the plurality of symbols includes a first symbol, a last symbol, and one or more middle symbols;
a history table comprising entries, wherein each entry comprises at least one symbol;
a plurality of comparators for comparing the plurality of symbols with entries in the history table, wherein the plurality of comparators are operable to compare each of the plurality of symbols with each entry in the history table concurrently, wherein the plurality of comparators produce compare results;
match information logic coupled to the plurality of comparators for determining match information for each of the plurality of symbols based on the compare results, wherein the match information logic is operable to determine if a contiguous match occurs for one or more of the one or more middle symbols that does not involve a match with either the first symbol or the last symbol; and
an output coupled to the match information logic for outputting compressed data in response to the match information.
72. The data compression system of claim 67,
wherein the one or more predetermined metrics comprise at least one of compression ratio and compression speed.
73. A data compression system comprising:
a first plurality of compression engines, wherein each of the first plurality of compression engines implements a different respective data compression algorithm, wherein at least one of the first plurality of compression engines implements a parallel data compression algorithm, and wherein each of the first plurality of compression engines is configured to:
receive uncompressed data; and
compress the uncompressed data using its respective data compression algorithm;

wherein the first plurality of compression engines produce a plurality of different versions of the compressed data; and
decision logic coupled to the first plurality of compression engines and configured to:
select one of the plurality of different versions of the compressed data based upon a plurality of predetermined metrics; and
output the selected compressed data.

The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

What is claimed is:

1. A reading defect detecting circuit of EEPROM comprising:
an ordinary read voltage generating circuit for generating a voltage to be used in ordinary reading of EEPROM which is the object of detection,
a defect detecting read voltage generating circuit for generating a defect detecting read voltage which is higher than the ordinary read voltage,
a selector for selecting a voltage to be applied to the EEPROM from the ordinary read voltage and defect detecting read voltage,
a control circuit for controlling the selection timing of this selector, and
a comparator for comparing first data and second data being read out by said EEPROM from the ordinary read voltage and defect detecting read voltage respectively selected by said selector.
2. The reading defect detecting circuit of EEPROM of claim 1, wherein said comparator includes an error flag generating circuit for generating an error flag when the first data and second data are not matched.
3. The reading defect detecting circuit of EEPROM of claim 1, wherein said comparator includes a data latch circuit and an address latch circuit for storing respectively the first data and its address in the EEPROM.
4. The reading defect detecting circuit of EEPROM of claim 1, wherein it is at least designed to repeat a period composed of a first timing for selecting the ordinary read voltage by said selector, a second timing for selecting the defect detecting read voltage by said selector, and a third timing for comparing the first and second data by said comparator.
5. The reading defect detecting circuit of EEPROM of claim 2, wherein said comparator includes a data latch circuit and an address latch circuit for storing respectively the first data and its address in the EEPROM.
6. The reading defect detecting circuit of EEPROM of claim 2, wherein it is at least designed to repeat a period composed of a first timing for selecting the ordinary read voltage by said selector, a second timing for selecting the defect detecting read voltage by said selector, and a third timing for comparing the first and second data by said comparator.
7. The reading defect detecting circuit of EEPROM of claim 3, wherein it is designed to repeat a period comprising at least a first timing for selecting the ordinary read voltage by said selector, a second timing for selecting the defect detecting read voltage by said selector, and a third timing for comparing the first and second data by said comparator.
8. A reading defect detecting method of EEPROM comprising the steps of:
reading out first data and second data respectively by applying an ordinary read voltage used as ordinary read voltage of EEPROM to be detected and a defect detecting read voltage higher than this ordinary read voltage sequentially into said EEPROM,
comparing the first data and second data, and
generating an error flag when the first data and second data are not matched at the comparing step.
9. The reading defect detecting method of EEPROM of claim 8, wherein, after an error flag is generated, the first data is written at the address in the EEPROM from which the first data and second data are read out.

1. A control process for controlling the combustion of an internal combustion engine with controlled ignition and liquid fuel direct injection, in which the engine comprises at least one cylinder with a combustion chamber, at least one intake means, at least one exhaust means and at least one direct injection means for liquid fuel in order to obtain a fuelair mixture in the combustion chamber, the control process comprising:
determining at least one operational zone of the engine in which particulates are emitted during combustion of the fuelair mixture; and
for operation of the engine in this determined zone, introducing into the combustion chamber another fuelair mixture resulting from indirect injection of a gaseous fuel comprising natural vehicle gas (NVG) or liquid petroleum gas (LPG).
2. The control process according to claim 1, wherein the fuelair mixture is obtained from a liquid gasoline fuel.
3. The control process according to claim 2, wherein the gaseous fuel comprises natural vehicle gas (NVG).
4. The control process according to claim 2, wherein the gaseous fuel comprises liquid petroleum gas (LPG).
5. The control process according to claim 1, wherein the gaseous fuel comprises natural vehicle gas (NVG).
6. The control process according to claim 1, wherein the gaseous fuel comprises liquid petroleum gas (LPG).
7. The control process according to claim 1, wherein determining the at least one operational zone comprises determining at least one operational zone from tests and storing the parameters for the at least one operational zone in an engine control unit.
8. The control process according to claim 1, wherein determining the at least one operational zone comprises determining at least one operational zone from a measurement carried out by a particulate sensor.
9. The control process according to claim 8, wherein the particulate sensor is provided in an exhaust line of the engine.
10. The control process according to claim 8, wherein the particulate sensor is provided in an exhaust manifold connected to the exhaust means.
11. A control process for controlling the combustion of an internal combustion engine with controlled ignition and liquid fuel direct injection, in which the engine comprises at least one cylinder with a combustion chamber, at least one intake comprising intake pipework and an intake valve, at least one exhaust and at least one direct injector for liquid fuel in order to obtain a first fuelair mixture in the combustion chamber, the control process comprising:
determining if the engine is operated in an operational zone of the engine in which particulates are emitted during combustion of the first fuelair mixture; and
if the engine is being operated in an operational zone of the engine in which particulates would be emitted by combustion of the fuelair mixture, indirectly injecting into the combustion chamber a gaseous fuel comprising natural vehicle gas (NVG) or liquid petroleum gas (LPG).
12. The control process according to claim 11, wherein the gaseous fuel comprises natural vehicle gas (NVG).
13. The control process according to claim 11, wherein the gaseous fuel comprises liquid petroleum gas (LPG).
14. The control process according to claim 11, wherein determining if the engine is operated in an operational zone of the engine in which particulates are emitted during combustion of the first fuelair mixture comprises determining if the engine is being operated within parameters stored in an engine control unit, the parameters being determined from tests.
15. The control process according to claim 11, wherein determining the at least one operational zone comprises determining at least one operational zone from a measurement carried out by a particulate sensor.
16. The control process according to claim 15, wherein the particulate sensor is provided in an exhaust line of the engine.
17. The control process according to claim 15, wherein the particulate sensor is provided in an exhaust manifold of the engine.
18. The control process according to claim 11, wherein the engine further comprises an engine control unit and a gaseous fuel injector configured to inject gaseous fuel into the intake pipework so as to obtain a second fuelair mixture that is then introduced into the combustion chamber when the intake valve opens, and wherein, if the engine is being operated in an operational zone of the engine in which particulates would be emitted by combustion of the fuelair mixture, the engine control unit controls the at least one direct injector for liquid fuel to reduce a quantity of liquid fuel introduced into the combustion chamber and controls the gaseous fuel injector to inject the gaseous fuel into the intake pipework so as to obtain the second fuelair mixture that is then introduced into the combustion chamber when the intake valve opens.

The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

1. A clock generator comprising:
a current controlled oscillator (ICO) having an input for receiving a control current, and an output for outputting clock signals of a frequency according to the control current; and
a biasing circuit electrically connected to the ICO comprising:
a controlled current generator having a first current output coupled to the input of the ICO for outputting the control current, and a second current output copying the first current output with a predetermined ratio;
a resistor having one end coupled to the second current output of the controlled current generator;
an operational amplifier (opamp) having a first input coupled to the second current output of the controlled current generator, a second input, and an output coupled to the controlled current generator;
a diode having an end coupled to the second input of the opamp; and
a current source having a first end coupled to the end of the diode and a second end coupled to the output of the opamp,
wherein substantially all of the current from the current source flows through the diode and substantially all of the current from second current output flows through the resistor.
2. The clock generator of claim 1 further comprising an inverter coupled to the output of the ICO.
3. The clock generator of claim 1 further comprising a buffer coupled to the output of the ICO.
4. The clock generator of claim 1 wherein the controlled current generator comprises:
a first PMOS comprising:
a source coupled to a voltage source;
a drain coupled to the input of the ICO; and
a gate coupled to the output of the opamp; and

a second PMOS comprising
a source coupled to the voltage source;
a drain coupled to the first input of the opamp; and
a gate coupled to the output of the opamp.
5. The clock generator of claim 1 wherein the current source is a PMOS, the first end of the current source being a drain of the PMOS, the second end of the current source being a gate of the PMOS.
6. The clock generator of claim 1 wherein the ICO is a ring oscillator.
7. The clock generator of claim 1 wherein the diode is a parasitic bipolar.
8. The clock generator of claim 1 wherein the first current output of the controlled current generator is substantially equal to the second current output of the controlled current generator with reduced low-frequency jitter.
9. A biasing circuit for controlling a current oscillator, the biasing circuit comprising:
a controlled current generator having a first current output for outputting a control current, and a second current output copying the first current output with a predetermined ratio;
a resistor having a first end coupled to the second current output of the controlled current generator, and a second end coupled to a first voltage;
an operational amplifier (opamp) having a first input coupled to the second current output of the controlled current generator, a second input, and an output electrically coupled to the controlled current generator;
a diode having a first end coupled to the second input of the opamp, and a second end coupled to said first voltage; and
a current source having a first end coupled to the end of the diode, a second end coupled to the output of the opamp, and a third end coupled to a second voltage,

wherein substantially all of the current from the current source flows through the diode and substantially all of the current from second current output flows through the resistor.
10. The biasing circuit of claim 9 wherein the controlled current generator comprises:
a first PMOS comprising:
a source coupled to said second voltage;
a drain for outputting the control current; and
a gate coupled to the output of the opamp; and

a second PMOS comprising
a source coupled to said second voltage;
a drain coupled to the first input of the opamp; and
a gate coupled to the output of the opamp.
11. The biasing circuit of claim 9 wherein the current source is a PMOS, the first end of the current source being a drain of the PMOS, the second end of the current source being a gate of the PMOS, the third end of the current source being a source of the PMOS.
12. The biasing circuit of claim 9 wherein the diode is a parasitic bipolar.
13. The biasing circuit of claim 9 wherein said second voltage is higher than said first voltage.
14. The biasing circuit of claim 9 wherein said first voltage is ground.