Data generator providing large amounts of data of arbitrary word length

1. A data generator comprising:

means for storing a plurality of data streams with each data stream having sets of M-bit parallel data (M is a natural number) defining a group of the parallel data;

means for storing sequence information and data discard information indicating how many data bits are discarded from the ending data bits in each data stream;

a sequence controller for providing address information derived from the sequence information to the parallel data storing means to read the data streams and providing the data discard information corresponding to the respective data streams;

means for shifting data in a next data stream according to the number of effective data bits of the last M-bit parallel data in a current data stream when said number of effective data bits is less than M based on the data discard information;

a data shift controller for generating data enables indicating the respective data in the data stream that are effective data bits and not-effective data bits based on the data discard information;

a data stream combiner for combining the effective data bits in the data streams from the data shifting means using the data enables to provide M-bit parallel data having only the effective data bits; and

a parallel to serial converter for converting the M-bit parallel data in the combined data streams to K-bit parallel data wherein K is a natural number equal to one and less than M.

2. The data generator as recited in claim 1 further comprising:

at least first and second buffers; and

a data timing controller;

wherein the sequence information storing means further stores data stream start and end information indicating the start of parallel data in each data stream and the end of parallel data in each data stream;

the data shift controller shifts the data stream end information to a location before the last parallel data in the data stream if the last parallel data has the effective data bits less than M based on the data discard information;

the first and second buffers sequentially receive the data streams from the data shifting means while receiving the data stream start and end information to provide the data streams; and

the data timing controller detects the data stream end information from one of the buffers to control the other buffer to initiate the providing of the next data stream in order to align timing of the last parallel data in the current data stream and the first parallel data in the next data stream.

3. The data generator as recited in claim 2 wherein the buffers comprise a plurality of First-In-First-Out (FIFO) buffers.

4. The data generator as recited in claim 1 wherein the data shifting means comprises is a barrel shifter for shifting the data bits in the next data stream as a function of the number of data bits determined by the data discard information.

5. The data generator as recited in claim 1 wherein the data shifting means further comprises a series of registers retaining a series of the M-bit parallel data for providing one set of the M-bit parallel data by selecting from the series of the M-bit parallel data.

6. The data generator as recited in claim 5 wherein the data shifting means further comprises a plurality of multiplexers for selecting one set of the M-bit parallel data from the series of the M-bit parallel data.

7. The data generator as recited in claim 1 wherein means for storing parallel data provides each data stream during a burst mode.

8. The data generator as recited in claim 1 wherein means for storing parallel data comprises one of a family of Double Data Rate Synchronous Dynamic Random Access Memory (DDR SDRAM).

9. A data generator comprising:

a reference clock generator for providing a reference clock;

a first clock generator for providing a first clock;

a second clock generator for providing a second clock that is derived from dividing the reference clock and having a frequency lower than that of the first clock;

means for storing a plurality of data streams with each data stream having sets of M-bit parallel data (M is a natural number) defining a group of the parallel data;

means for storing sequence information and data discard information indicating how many data bits are discarded from the ending data bits in each data stream;

a sequence controller for providing address information derived from the sequence information to the parallel data storing means to read the data streams and providing the data discard information corresponding to the respective data streams;

means for shifting data in a next data stream according to the number of effective data bits of the last M-bit parallel data in a current data stream when said number of effective data bits is less than M based on the data discard information;

a data shift controller for generating data enables indicating the respective data in the data stream that are effective data bits and not-effective data bits based on the data discard information;

at least first and second buffers for sequentially receiving the data streams from the data shifting means according to the first clock and receiving data stream start and end information to provide the data streams according to the second clock;

a data stream combiner for combining effective data bits in the data streams from the data shifting means using the data enables to provide M-bit parallel data having only the effective data bits; and

a parallel to serial converter receiving the M-bit parallel data in the combined data streams according to the second clock and providing K-bit parallel data according to the reference clock wherein K is a natural number equal to one and less than M.

10. The data generator as recited in claim 9 wherein the first and second buffers sequentially provide time aligning of the data stream of the last parallel data in the current data stream to that of the first parallel data in the next data stream if the number of the effective data bits in the last parallel data in the current data stream is less than M.

11. The data generator as recited in claim 9 wherein the buffers comprise a plurality of asynchronous First-In-First-Out (FIFO) buffers.

12. The data generator as recited in claim 9 wherein the data shifting means comprises is a barrel shifter for shifting the data bits in the next data stream as a function of the number of data bits determined by the data discard information.

13. The data generator as recited in claim 9 wherein the data shifting means further comprises a series of registers retaining a series of the M-bit parallel data for providing one set of the M-bit parallel data by selecting from the series of the M-bit parallel data.

14. The data generator as recited in claim 13 wherein the data shifting means further comprises a plurality of multiplexers for selecting one set of the M-bit parallel data from the series of the M-bit parallel data.

15. The data generator as recited in claim 9 wherein means for storing parallel data provides each data stream during the burst mode.

16. The data generator as recited in claim 9 wherein means for storing parallel data comprise one of a family of Double Data Rate Synchronous Dynamic Random Access Memory (DDR SDRAM).