Data processing apparatus and system and method for controlling memory access

1 . A data processor apparatus comprising a plurality of processing elements, a memory having a plurality of storage elements arranged in a plurality of columns, a plurality of column decoders, a plurality of memory ports coupled to said decoders for at least one outputting data from said memory and receiving data for said memory, each of said plurality of memory ports being couplable to at least a respective one of said plurality of processor elements such that each processor element is capable of accessing at least one column of storage elements,

a device for accessing said memory,

switch means for switchably coupling each one of said plurality of memory ports to a respective processing element and for switchably coupling each one of said plurality of memory ports to said device, and

a memory access controller arranged to control said switch means to selectively couple said plurality of memory ports to one of (i) said device and (ii) said plurality of processor elements.

2 . A data processor apparatus as claimed in claim 1 , further comprising a data bus for coupling said memory ports to said device and further comprising a bus decoder for coupling selected memory ports to said data bus.

3 . A data processor apparatus as claimed in claim 2 , wherein said data bus comprises a plurality of bus lines, and said bus decoder is arranged to selectively couple selected memory ports to selected bus lines.

4 . A data processor apparatus as claimed in claim 3 , wherein the number of memory ports is greater than the number of bus lines.

5 . A data processor apparatus as claimed in claim 2 , wherein said data bus comprises a plurality of bus lines, and said bus decoder is arranged to selectively couple selected bus lines to said plurality of memory ports.

6 . A data processor apparatus as claimed in claim 5 , wherein the number of bus lines is greater than the number of memory ports.

7 . A data processor apparatus as claimed in claim 1 , further comprising a data bus for coupling said memory ports to said device, said data bus having a plurality of bus lines wherein the number of bus lines is different to the number of memory ports, and decoding means between said memory ports and said data bus for one of coupling selected ones of said memory ports to said bus lines, if the number of memory ports exceeds the number of bus lines, and coupling selected ones of said bus lines to said memory ports, if the number of bus lines exceeds the number of memory ports.

8 . A data processor apparatus as claimed in claim 1 , wherein said processing elements are arranged to perform operations when said plurality of memory ports are coupled to said device.

9 . A data processor apparatus as claimed in claim 8 , wherein said processing elements are arranged to process data previously read from said memory when said plurality of memory ports are coupled to said device.

10 . A data processor apparatus as claimed in claim 1 , further comprising at least one storage element for storing data received from a memory port before being processed by a respective processor element.

11 . A data processor apparatus as claimed in claim 10 , comprising at least one respective storage element coupled to each of said plurality of memory ports for storing data received from said memory ports before being processed by said plurality of processor elements.

12 . A data processor apparatus as claimed in claim 11 , comprising two or more storage elements for storing data from each of said plurality of memory ports before being processed by said processor elements.

13 . A data processor apparatus as claimed in claim 1 wherein said device comprises a processor, a direct memory access (DMA) device or an input/output (I/O) device.

14 . A data processor apparatus as claimed in claim 2 , further comprising another device coupled to said data bus.

15 . A data processor apparatus as claimed in claim 1 , wherein said memory ports each comprise an I/O port.

16 . A data processor apparatus as claimed in claim 1 , wherein said memory comprises a random access memory (RAM) and each of said memory ports comprises an input/output (I/O) port of said RAM.

17 . A data processor apparatus as claimed in claim 1 , wherein each of said memory ports comprises a one-bit memory port and further comprising a single bit line of a parallel data bus between each memory port and a respective processor element for one of read access and write access.

18 . A data processor apparatus as claimed in claim 2 , further comprising an array controller coupled to said data bus for controlling parallel operations of said processing elements.

19 . A data processor apparatus as claimed in claim 1 , further comprising a data bus for coupling said memory ports to said device and an array controller coupled to said data bus for controlling parallel operations of said processor elements.

20 . A device comprising a memory having a plurality of memory ports for at least one of outputting data from said memory and receiving data for said memory, a data bus having a plurality of bus lines, wherein the number of bus lines is different to the number of memory ports, and decoding means between said memory ports and said data bus for one of coupling selected ones of said memory ports to said bus lines, if the number of memory ports exceeds the number of bus lines, and coupling selected ones of said bus lines to said memory ports, if the number of bus lines exceeds the number of memory ports.

21 . A device as claimed in claim 20 , further comprising a processor coupleable to said plurality of memory ports, independently of said data bus.

22 . A device as claimed in claim 21 , wherein said processor comprises a plurality of processing elements, each coupleable to a respective memory port.

23 . A device as claimed in claim 21 , further comprising memory access control means for selectively coupling one of said data bus and said processor to said memory ports.