Programmable switch for FPGA input/output signals
First Claim
1. A programmable logic device comprising:
- a user logic structure;
a configuration memory for controlling said user logic structure;
structure for accessing said configuration memory;
a plurality of pads for connecting external signals to said programmable logic device;
a programmable switch, said programmable switch being programmable to connect signals between said pads, said user logic structure, and said structure for accessing said configuration memory, said programmable switch being programmed by said configuration memory.
1 Assignment
0 Petitions
Accused Products
Abstract
A programmable switch for a field programmable gate array (FPGA) allows a user to reconfigure or partly reconfigure the FPGA from within the FPGA, allows an addressable configuration memory to be addressed through a set of pins for configuration and through user logic for reconfiguration. The same pins can be used for both configuration and user logic. Also signals such as chip enable and other control signals can be modified by user logic before performing their function so that chips external to the FPGA can be eliminated. Upon power-up of the chip, each programmable switch connects its pad to the programming logic which programs configuration memory, so that the programming logic can receive instructions from an external source and control programming of the core logic of the chip. The configuration memory programs not only the internal circuitry accessed by the user but also the programmable switch itself. Thus as configuration proceeds, or after configuration is completed, the programmable switch can be reconfigured to connect internal portions of the FPGA user logic to parts of the configuration memory which were initially loaded from external pins.
134 Citations
59 Claims
-
1. A programmable logic device comprising:
-
a user logic structure;
a configuration memory for controlling said user logic structure;
structure for accessing said configuration memory;
a plurality of pads for connecting external signals to said programmable logic device;
a programmable switch, said programmable switch being programmable to connect signals between said pads, said user logic structure, and said structure for accessing said configuration memory, said programmable switch being programmed by said configuration memory. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A programmable logic device comprising:
- 8. A programmable logic device comprising:
- 14. A programmable logic device comprising:
-
20. A programmable logic device comprising:
-
21. A programmable logic device comprising:
-
22. A programmable logic device comprising:
-
23. A programmable logic device comprising:
-
24. A programmable logic device comprising:
-
25. A programmable logic device comprising:
-
26. A programmable logic device comprising:
-
27. A programmable logic device comprising:
-
28. A programmable logic device comprising:
-
29. A programmable logic device comprising:
-
30. A programmable logic device comprising:
-
31. A programmable logic device comprising:
-
32. In a programmable logic device comprising:
-
a) a user logic section having user memory devices;
b) a configuration memory comprising a set of memory cells for storing configuration data and for controlling the function performed by the user logic; and
c) a configuration memory interface circuit for loading data into or reading data out of said configuration memory, - View Dependent Claims (33, 34, 35, 36, 37, 38)
-
- 39. A programmable logic device comprising:
-
43. Programmable logic device comprising:
-
44. In a circuit comprising a) at least one bit line;
- b) a set of memory cells; and
c) a set of switches for coupling said memory cells to said bit line, a method for setting said memory cells to a logic value comprising;
- View Dependent Claims (45)
- b) a set of memory cells; and
-
46. Structure comprising:
-
47. Structure comprising:
- 48. In a system comprising a configuration data source and a programmable logic device, and said programmable logic device comprising a register storing identifying data, a method comprising:
- 50. In a system comprising a configuration data source and a programmable logic device, a method comprising:
-
52. In a system comprising a configuration data source and a programmable logic device, a method comprising:
-
53. In a system comprising a programmable logic device, a method comprising:
- 54. A system comprising:
-
56. A system comprising:
-
57. A system comprising:
-
58. A system comprising:
-
59. In a programmable logic device having configuration memory, logic, and pads, a switch programmable to connect:
Specification