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US5652904A Expired / Lapsed US ⏱️ 0.0 years remaining

Non-reconfigurable microprocessor-emulated FPGA

Assignee: Xilinx Inc
•
Filing: 1995-06-02
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Granted: 1997-07-29
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Expires: 2015-06-02
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Abstract

Abstract In accordance with the present invention, a microprocessor controlled device is provided which appears to a user to be a programmable logic device. Signals are taken from and placed on external pins in the same manner as would be done with a prior art programmable logic device. However, internal hardware which would be provided in a programmable logic device for performing the logic function is replaced by a microprocessor with associated memory. The microprocessor is programmable to read input signals from input pins, perform calculations related to the desired logic, and place signals onto output pins. Thus the function of the microprocessor controlled device as it appears from observing signals on external pins is the same as that of a prior art FPGA or other logic device. However, internally, a program which has been stored in the memory associated with the microprocessor causes the microprocessor to serially read signals from external pins, perform the necessary calculations, and place signals onto output pins. Multiple microprocessors in the same logic device can also be provided.

Inventors

  • 👤 Stephen M. Trimberger

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 07:25
CPC Classifications
H; H03; H03K; H03K19/00; H03K19/02; H03K19/173; H03K19/177; H03K19/17736; H03K19/17744; G; G06; G06F; G06F15/00; G06F15/76; G06F15/78; G06F15/7807; G06F15/7814; G06F15/7867; H03K19/1733; H03K19/1737; H03K19/17724; H03K19/17732

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 104 words
An integrated circuit for emulating a reconfigurably programmed logic device, said circuit comprising: a non-reconfigurable microprocessor an internal bus comprising a plurality of conductive lines; a plurality of pins or pads; a plurality of input/output blocks, each input/output block having a plurality of leads each connected to a line of said bus and at least one lead connected to one of said pins or pads; means for connecting at least one lead of said microprocessor to a corresponding one of said conductive lines in said bus; means for storing a set of instructions for controlling said microprocessor to function as said reconfigurably programmable device.
Claim 2
Dependent Claim 104 words
An integrated circuit for emulating a reconfigurably programmed logic device, said circuit comprising: a non-reconfigurable microprocessor an internal bus comprising a plurality of conductive lines; a plurality of pins or pads; a plurality of input/output blocks, each input/output block having a plurality of leads each connected to a line of said bus and at least one lead connected to one of said pins or pads; means for connecting at least one lead of said microprocessor to a corresponding one of said conductive lines in said bus; means for storing a set of instructions for controlling said microprocessor to function as said reconfigurably programmable device.
Claim 3
Dependent Claim 32 words
The integrated circuit as in claim 1 in which said means for connecting at least one lead of said microprocessor comprises means for accessing a plurality of conductive lines in said bus.
Claim 4
Dependent Claim 24 words
The integrated circuit as in claim 1 further comprising: means (102) for storing signals generated by said microprocessor and means for reading said signals.
Claim 5
Dependent Claim 19 words
The integrated circuit as in claim 1 in which said input/output block comprises at least one output storage register.
Claim 6
Dependent Claim 39 words
The integrated circuit as in claim 4 in which said input/output block comprises a first output storage register for storing data to apply to an external pin and a second output storage register for controlling application to said pin.
Claim 7
Dependent Claim 32 words
The integrated circuit as in claim 5 further comprising a three-state buffer at an output of said first storage register and in which a second output storage register controls said three-state buffer.
Claim 8
Dependent Claim 19 words
The integrated circuit as in claim 1 in which said input/output block comprises at least one input storage register.
Claim 9
Dependent Claim 23 words
The integrated circuit as in claim 7 in which said input/output block further comprises counter means (201) for enabling said input storage register.
Claim 10
Dependent Claim 50 words
The integrated circuit as in claim 8 in which said counter means comprises: a counter, and a set/reset latch; said bus comprises an address bus, and a data bus; and said data bus loads said counter in parallel, said address bus starts said counter, and said counter resets said latch.
Claim 11
Dependent Claim 23 words
The integrated circuit as in claim 7 in which said input/output block further comprises a three-state buffer loaded by said input storage register.
Claim 12
Dependent Claim 17 words
The integrated circuit as in claim 1 in which said input/output block comprises an input three-state buffer.
Claim 13
Dependent Claim 20 words
A programmable integrated circuit as in claim 11 in which said input three-state buffer is addressed through an address bus.
Claim 14
Dependent Claim 31 words
The integrated circuit as in claim 1 in which an instruction in said set of instructions includes a look up table which defines a function to be performed in said instruction.
Claim 15
Dependent Claim 24 words
The integrated circuit as in claim 1 in which an instruction in said set of instructions identifies plural ports for reading and writing data.
Claim 16
Dependent Claim 16 words
The integrated circuit as in claim 1 in which said microprocessor comprises a plurality of microprocessors.
Claim 17
Dependent Claim 27 words
The integrated circuit as in claim 15 in which any one of said pins or pads is written to by only one of said plurality of microprocessors.
Claim 18
Dependent Claim 38 words
The integrated circuit as in claim 15 further comprising a memory having a plurality of memory cells, in which any one of said cells in said memory is written to by only one of said plurality of microprocessors.
Claim 19
Dependent Claim 22 words
The integrated circuit as in claim 1 in which an instruction calls out three addresses, two for input and one for output.
Claim 20
Dependent Claim 22 words
The integrated circuit as in claim 18 in which both of said input addresses access memory cells simultaneously through separate memory ports.
Claim 21
Dependent Claim 22 words
The integrated circuit as in claim 1 in which an instruction calls out four addresses, three for input and one for output.
Claim 22
Dependent Claim 47 words
The integrated circuit as in claim 1 in which at least one of said input/output blocks comprises a plurality of flip flops for loading a plurality of data bits in a single cycle of a clock signal controlling said flip flops in response to a single address.
Claim 23
Dependent Claim 51 words
The integrated circuit as in claim 21 in which said plurality of data bits are shifted to an external pin under control of said clock signal controlling said flip flops, and said clock signal controlling said flip flops switches at a rate different from a clock signal which controls said microprocessor.
Claim 24
Dependent Claim 107 words
An integrated circuit for emulating a programmably reconfigurable logic device, said circuit comprising: a non-reconfigurable microprocessor an internal bus comprising a plurality of conductive lines; a plurality of pins or pads; a plurality of input/output blocks, each input/output block having a plurality of leads each connected to a line of said bus and at least one lead connected to one of said pins or pads; an interconnect structure for connecting at least one lead of said microprocessor to a corresponding one of said conductive lines in said bus; a memory for storing a set of instructions for controlling said microprocessor for operation that emulates said programmable device.
Claim 25
Dependent Claim 107 words
An integrated circuit for emulating a programmably reconfigurable logic device, said circuit comprising: a non-reconfigurable microprocessor an internal bus comprising a plurality of conductive lines; a plurality of pins or pads; a plurality of input/output blocks, each input/output block having a plurality of leads each connected to a line of said bus and at least one lead connected to one of said pins or pads; an interconnect structure for connecting at least one lead of said microprocessor to a corresponding one of said conductive lines in said bus; a memory for storing a set of instructions for controlling said microprocessor for operation that emulates said programmable device.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-07-28 2001-01-27 2001-07-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-07-28 2005-01-27 2005-07-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-07-28 2009-01-27 2009-07-29 $7700.00 Window Closed / Lapsed

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