Parameterizable Macros for Intel® FPGAs User Guide

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Date 10/02/2023
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Document Table of Contents
Document Table of Contents x
1. Answers to Top FAQs 2. Parameterizable Macros for Intel FPGAs Overview 3. Dual-Port Random Access Memory (RAM) Parameterizable Macros 4. FIFO Parameterizable Macros 5. I/O PLL Parameterizable Macros 6. CDC Parameterizable Macros 7. Document Revision History for the Parameterizable Macros for Intel FPGAs User Guide 8. Parameterizable Macros for Intel FPGAs User Guide Archives
2. Parameterizable Macros for Intel FPGAs Overview x
2.1. Available Parameterizable Macros for Intel FPGAs 2.2. Inserting HDL Code from Parameterizable Macro Templates
3. Dual-Port Random Access Memory (RAM) Parameterizable Macros x
3.1. Simple Dual-Port RAM Parameterizable Macro (simple_dual_port_ram) 3.2. True Dual-Port RAM Parameterizable Macro (true_dual_port_ram)
3.1. Simple Dual-Port RAM Parameterizable Macro (simple_dual_port_ram) x
3.1.1. Simple Dual-Port RAM Parameterizable Macro Port Descriptions 3.1.2. Simple Dual-Port RAM Parameterizable Macro Parameters 3.1.3. Simple Dual-Port RAM VHDL Instantiation Template 3.1.4. Simple Dual-Port RAM Verilog Instantiation Template 3.1.5. Simple Dual-Port RAM SystemVerilog Instantiation Template
3.2. True Dual-Port RAM Parameterizable Macro (true_dual_port_ram) x
3.2.1. True Dual-Port RAM Parameterizable Macro Port Descriptions 3.2.2. True Dual-Port RAM Parameterizable Macro Parameters 3.2.3. True Dual-Port RAM VHDL Instantiation Template 3.2.4. True Dual-Port RAM Verilog Instantiation Template 3.2.5. True Dual-Port RAM SystemVerilog Instantiation Template
4. FIFO Parameterizable Macros x
4.1. Synchronous FIFO Parameterizable Macro (sync_fifo) 4.2. Asynchronous FIFO Parameterizable Macro (async_fifo)
4.1. Synchronous FIFO Parameterizable Macro (sync_fifo) x
4.1.1. Synchronous FIFO Parameterizable Macro Port Descriptions 4.1.2. Synchronous FIFO Parameterizable Macro Parameters 4.1.3. Synchronous FIFO VHDL Instantiation Template 4.1.4. Synchronous FIFO Verilog Instantiation Template 4.1.5. Synchronous FIFO SystemVerilog Instantiation Template
4.2. Asynchronous FIFO Parameterizable Macro (async_fifo) x
4.2.1. Asynchronous FIFO Parameterizable Macro Port Descriptions 4.2.2. Asynchronous FIFO Parameterizable Macro Parameters 4.2.3. Asynchronous FIFO VHDL Instantiation Template 4.2.4. Asynchronous FIFO Verilog Instantiation Template 4.2.5. Asynchronous FIFO SystemVerilog Instantiation Template
5. I/O PLL Parameterizable Macros x
5.1. I/O PLL Parameterizable Macro Port Descriptions 5.2. I/O PLL Parameterizable Macro Parameters 5.3. Basic I/O PLL VHDL Instantiation Template 5.4. Basic I/O PLL Verilog Instantiation Template 5.5. Basic I/O PLL SystemVerilog Instantiation Template
6. CDC Parameterizable Macros x
6.1. Synchronous Reset Synchronizer Parameterizable Macro (ipm_cdc_sync_rst) 6.2. Asynchronous Reset Synchronizer Parameterizable Macro (ipm_cdc_async_rst) 6.3. Synchronizer Using Single Clock Parameterizable Macro (ipm_cdc_1clk_sync) 6.4. Synchronizer Using Two Clocks Parameterizable Macro (ipm_cdc_2clks_sync) 6.5. Glitchless Clock MUX Parameterizable Macro (ipm_cdc_glitchless_clk_mux) 6.6. Bus Synchronizer Parameterizable Macro (ipm_cdc_bus_sync)
6.1. Synchronous Reset Synchronizer Parameterizable Macro (ipm_cdc_sync_rst) x
6.1.1. Synchronous Reset Synchronizer Parameterizable Macro Port Descriptions 6.1.2. Synchronous Reset Synchronizer Parameterizable Macro Parameters 6.1.3. Synchronous Reset Synchronizer VHDL Instantiation Template 6.1.4. Synchronous Reset Synchronizer Verilog Instantiation Template 6.1.5. Synchronous Reset Synchronizer SystemVerilog Instantiation Template
6.2. Asynchronous Reset Synchronizer Parameterizable Macro (ipm_cdc_async_rst) x
6.2.1. Asynchronous Reset Synchronizer Parameterizable Macro Port Descriptions 6.2.2. Asynchronous Reset Synchronizer Parameterizable Macro Parameters 6.2.3. Asynchronous Reset Synchronizer VHDL Instantiation Template 6.2.4. Asynchronous Reset Synchronizer Verilog Instantiation Template 6.2.5. Asynchronous Reset Synchronizer SystemVerilog Instantiation Template
6.3. Synchronizer Using Single Clock Parameterizable Macro (ipm_cdc_1clk_sync) x
6.3.1. Synchronizer Using Single Clock Parameterizable Macro Port Descriptions 6.3.2. Synchronizer Using Single Clock Parameterizable Macro Parameters 6.3.3. Synchronizer Using Single Clock VHDL Instantiation Template 6.3.4. Synchronizer Using Single Clock Verilog Instantiation Template 6.3.5. Synchronizer Using Single Clock SystemVerilog Instantiation Template
6.4. Synchronizer Using Two Clocks Parameterizable Macro (ipm_cdc_2clks_sync) x
6.4.1. Synchronizer Using Two Clocks Parameterizable Macro Port Descriptions 6.4.2. Synchronizer Using Two Clocks Parameterizable Macro Parameters 6.4.3. Synchronizer Using Two Clocks VHDL Instantiation Template 6.4.4. Synchronizer Using Two Clocks Verilog Instantiation Template 6.4.5. Synchronizer Using Two Clocks SystemVerilog Instantiation Template
6.5. Glitchless Clock MUX Parameterizable Macro (ipm_cdc_glitchless_clk_mux) x
6.5.1. Glitchless Clock MUX Parameterizable Macro Port Descriptions 6.5.2. Glitchless Clock MUX Parameterizable Macro Parameters 6.5.3. Glitchless Clock MUX VHDL Instantiation Template 6.5.4. Glitchless Clock MUX Verilog Instantiation Template 6.5.5. Glitchless Clock MUX SystemVerilog Instantiation Template
6.6. Bus Synchronizer Parameterizable Macro (ipm_cdc_bus_sync) x
6.6.1. Bus Synchronizer Parameterizable Macro Port Descriptions 6.6.2. Bus Synchronizer Parameterizable Macro Parameters 6.6.3. Bus Synchronizer VHDL Instantiation Template 6.6.4. Bus Synchronizer Verilog Instantiation Template 6.6.5. Bus Synchronizer SystemVerilog Instantiation Template
1. Answers to Top FAQs
2. Parameterizable Macros for Intel FPGAs Overview
3. Dual-Port Random Access Memory (RAM) Parameterizable Macros
4. FIFO Parameterizable Macros
5. I/O PLL Parameterizable Macros
6. CDC Parameterizable Macros
7. Document Revision History for the Parameterizable Macros for Intel FPGAs User Guide
8. Parameterizable Macros for Intel FPGAs User Guide Archives

4.2.1. Asynchronous FIFO Parameterizable Macro Port Descriptions

Table 7.  ASYNC_FIFO Parameterizable Macro Port Descriptions
Port Type Required Description
wrclk Input Yes Positive-edge-triggered clock.

Use to synchronize the following ports:

  • data
  • wrreq
  • wrfull
  • wrempty
  • wrusedw
rdclk Input Yes Positive-edge-triggered clock.

Use to synchronize the following ports:

  • q
  • rdreq
  • rdfull
  • rdempty
  • rdusedw
data Input Yes Holds the data that is written in the FIFO when the wrreq signal is asserted. The port width is equal to the DATA_WIDTH parameter.
wrreq Input Yes Assert this signal to request for a write operation.

Ensure that the following conditions are met:

  • Do not assert the wrreq signal when the wrfull port is high. Enable the overflow protection circuitry or set the OVERFLOW_CHECKING parameter to ON so that the FIFO can automatically disable the wrreq signal when it is full.
  • The wrreq signal must meet the functional timing requirement based on the full or wrfull signal.
  • Do not assert the wrreq signal during the deassertion of the aclr signal. Violating this requirement creates a race condition between the falling edge of the aclr signal and the rising edge of the write clock if the wrreq port is set to high.
  • Set the WRITE_ACLR_SYNCH parameter to ON to synchronize the aclr signal with the wrclk clock.
rdreq Input Yes Assert this signal to request for a read operation. The rdreq signal acts differently in normal mode and show-ahead mode.

Ensure that the following conditions are met:

  • Do not assert the rdreq signal when the rdempty port is high. Enable the underflow protection circuitry or set the UNDERFLOW_CHECKING parameter to ON so that the FIFO can automatically disable the rdreq signal when it is empty.
  • The rdreq signal must meet the functional timing requirement based on the rdempty signal.
aclr Input No Assert this signal to clear all the output status ports, but the effect on the q output may vary for different FIFO configurations.
q Output Yes

Shows the data read from the read request operation.

The width of the q port must be equal to the width of the data port. The port width is equal to the DATA_WIDTH_A parameter. For the mixed width FIFO, the width of the q port can be different from the width of the data port. You need to ensure the width of the q port is equal to the DATA_WIDTH_B parameter. The FIFO macro supports a wide write port with a narrow read port, and vice versa. However, the width ratio is restricted by the type of RAM block, and in the power of 2.

wrfull

rdfull

Output No

When asserted, the FIFO is considered full. Do not perform write request operation when the FIFO is full.

The rdfull signal functions as a combinational output instead of a derived version of the wrfull signal. Therefore, you must always refer to the wrfull port to ensure whether or not a valid write request operation can be performed, regardless of the target device.

wrempty

rdempty

Output No

When asserted, the FIFO is considered empty. Do not perform read request operation when the FIFO is empty.

The wrempty signal functions as a combinational output instead of a derived version of the rdempty signal. Therefore, you must always refer to the rdempty port to ensure whether or not a valid read request operation can be performed, regardless of the target device.

wrusedw

rdusedw

Output No Show the number of words stored in the FIFO.

Ensure that the wrusedw port width is equal to the ADDR_WIDTH_A parameter, and the rdusedw port width is equal to the ADDR_WIDTH_B parameter. For the ASYNC_FIFO_MIXED_WIDTH function, the width of the wrusedw and rdusedw ports must be equal to the ADDR_WIDTH_A and ADDR_WIDTH_B parameters, respectively.

The FIFO shows full even before the number of words stored reaches its maximum value. Therefore, you must always refer to the wrfull port for valid write request operation, and the rdempty port for valid read request operation regardless of the target device.

byteena Input Yes

Byte enable port at Port A to masks the data_a port so that only specific bits of data are written to the memory.

This port is enabled in FIFO because the pseudo RAM supports data with byte_size.

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