Techniques for optimizing design of a hard intellectual property block for data transmission

• US 7,434,192 B2
• Filed: 12/13/2004
• Issued: 10/07/2008
• Est. Priority Date: 12/13/2004
• Status: Expired due to Fees

• Current Assignee: Altera Corporation (Intel Corporation)
• Original Assignee: Altera Corporation (Intel Corporation)
• Inventors: Wortman, Curt, Chong, Thow-Pang, Ang, Boon-Jin, Burney, Ali, van Wageningen, Darren, Mansur, Dan
• Primary Examiner(s): Kik; Phallaka
• Application Number:
  US11/011,543
• Publication Number:
  US 20060125517A1
• Time in Patent Office: 1,394 Days
• Field of Search: 716/1, 716/16, 716/18, 710/305, 710/316, 710/20, 370/516, 370/503, 375/364, 375/365, 326/26, 326/41, 326/47
• US Class Current: 716/138
• CPC Class Codes: H04L 25/14 Channel dividing arrangements , i.e. in which a single bit stream is divided between several baseband channels and reassembled at the receiver

Abstract

Techniques are provided for implementing channel alignment for a data transmission interface in an HIP block on a programmable logic integrated circuit. The HIP block channel alignment logic can be run using a reduced number of parallel data paths, which consumes substantially less logic resources. Also, the HIP block channel alignment logic circuits can be processed at the higher HIP core clock rate in serial, decreasing lock latency time. Techniques are provided for implementing error handling for transmitted data in programmable logic circuits. The programmable logic circuits can be configured to implement error generation and error monitoring functions that are tailored for any application. Alternatively, the logic elements can be configured to perform other functions for applications that do not require error handling. The phase skew between data and clock signals on an integrated circuit are reduced by routing clock signals along with the data signals to each circuit block.

Claims

1. A programmable logic integrated circuit comprising a hard intellectual property (HIP) block designed to transmit data along parallel data channels, the hard intellectual property block comprising:

an oversampler that reduces clock skew between a clock signal and data in a first set of parallel data channels;

a down converter coupled to the oversampler that converts the data from the first set of parallel data channels to a second set of parallel data channels that have less parallel data channels than the first set; and

a channel alignment block coupled to the down converter that aligns corresponding data bits on the second set of parallel data channels.

2. The programmable logic integrated circuit defined in claim 1 wherein the channel alignment block compares data bytes between the data channels to specific patterns to byte align the data channels.

3. The programmable logic integrated circuit defined in claim 1 wherein the down converter transmits data to the second set of parallel data channels at a first clock frequency of the HIP block that is faster than a second clock frequency of data on the first set of parallel data channels.

4. The programmable logic integrated circuit defined in claim 1 wherein the HIP block further comprises:

an input/output interface block that receives data from off-chip and generates the first set of parallel data channels.

5. The programmable logic integrated circuit defined in claim 4 wherein the input/output interface block includes a first deserializer that generates the first set of parallel data channels.

6. The programmable logic integrated circuit defined in claim 4 wherein the HIP block further comprises a transmitter coupled to the channel alignment block that encodes packets of data into a SPI4-2 compatible data protocol;

and a receiver that extracts data packets from SPI4-2 compatible data.

7. The programmable logic integrated circuit defined in claim 6 wherein the HIP block further comprises:

a first FIFO buffer coupled to inputs of the transmitter for performing data for rate adaptation; and

a second FIFO buffer coupled to outputs of the receiver for performing data rate adaptation.

8. The programmable logic integrated circuit defined in claim 7 further comprising:

a set of programmable logic circuits configured as an error generator block that transmits errors to the first FIFO buffer; and

a data interface coupled between the first FIFO buffer in the HIP block and the error generator block.

9. The programmable logic integrated circuit defined in claim 7 further comprising:

a set of programmable logic circuits configured as an error monitor that monitors data output from the second FIFO buffer; and

a data interface coupled between the second FIFO buffer in the HIP block and the error monitor block.

10. A method for performing channel alignment on a hard intellectual property (HIP) block of a programmable logic integrated circuit, the HIP block designed to transmit data along parallel data channels, the method comprising:

oversampling a clock signal to reduce clock skew between the clock signal and the data received on a first set of parallel data channels;

converting the data on the first set of parallel data channels to a second set of parallel data channels that have less parallel data channels than the first set; and

aligning corresponding data bits in the second set of parallel data channels using channel alignment circuitry in the HIP block.

11. The method according to claim 10 further comprising:

deserializing serial data to generate the first set of parallel data channels.

12. The method according to claim 10 further comprising:

encoding packets of the data into a SPI4-2 compatible data protocol for transmission outside the integrated circuit.

13. The method according to claim 12 further comprising:

storing data received from logic on the programmable logic integrated circuit in a FIFO before the data is encoded into the SP14-2 compatible data protocol.

14. The method according to claim 13 further comprising:

storing the data packets in a FIFO buffer; and

transmitting the data packets to logic on the programmable logic integrated circuit.

15. The method according to claim 10 further comprising:

extracting data packets from SPI4-2 compatible data received from the channel alignment circuitry.