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1. Intel® Stratix® 10 Embedded Memory Overview
2. Intel® Stratix® 10 Embedded Memory Architecture and Features
3. Intel® Stratix® 10 Embedded Memory Design Considerations
4. Intel® Stratix® 10 Embedded Memory IP References
5. Intel Stratix 10 Embedded Memory Design Example
6. Intel® Stratix® 10 Embedded Memory User Guide Archives
7. Document Revision History for the Intel® Stratix® 10 Embedded Memory User Guide
2.1. Byte Enable in Intel® Stratix® 10 Embedded Memory Blocks
2.2. Address Clock Enable Support
2.3. Asynchronous Clear and Synchronous Clear
2.4. Memory Blocks Error Correction Code Support
2.5. Force-to-Zero
2.6. Coherent Read Memory
2.7. Freeze Logic
2.8. True Dual Port Dual Clock Emulator
2.9. 'X' Propagation Support in Simulation
2.10. Intel® Stratix® 10 Supported Embedded Memory IPs
2.11. Intel® Stratix® 10 Embedded Memory Clocking Modes
2.12. Intel® Stratix® 10 Embedded Memory Configurations
2.13. Initial Value of Read and Write Address Registers
3.1. Consider the Memory Block Selection
3.2. Consider the Concurrent Read Behavior
3.3. Customize Read-During-Write Behavior
3.4. Consider Power-Up State and Memory Initialization
3.5. Reduce Power Consumption
3.6. Avoid Providing Non-Deterministic Input
3.7. Avoid Changing Clock Signals and Other Control Signals Simultaneously
3.8. Including the Reset Release Intel® FPGA IP in Your Design
3.9. Resource and Timing Optimization Feature in MLAB Blocks
3.10. Consider the Memory Depth Setting
4.1.1. Release Information for RAM and ROM Intel® FPGA IPs
4.1.2. RAM: 1-PORT Intel® FPGA IP Parameters
4.1.3. RAM: 2-PORT Intel® FPGA IP Parameters
4.1.4. RAM: 4-PORT Intel® FPGA IP Parameters
4.1.5. ROM: 1-PORT Intel® FPGA IP Parameters
4.1.6. ROM: 2-PORT Intel® FPGA IP Parameters
4.1.7. RAM and ROM Interface Signals
4.1.8. Changing Parameter Settings Manually
4.3.1. Release Information for FIFO Intel® FPGA IP
4.3.2. Configuration Methods
4.3.3. Specifications
4.3.4. FIFO Functional Timing Requirements
4.3.5. SCFIFO ALMOST_EMPTY Functional Timing
4.3.6. FIFO Output Status Flag and Latency
4.3.7. FIFO Metastability Protection and Related Options
4.3.8. FIFO Synchronous Clear and Asynchronous Clear Effect
4.3.9. SCFIFO and DCFIFO Show-Ahead Mode
4.3.10. Different Input and Output Width
4.3.11. DCFIFO Timing Constraint Setting
4.3.12. Coding Example for Manual Instantiation
4.3.13. Design Example
4.3.14. Gray-Code Counter Transfer at the Clock Domain Crossing
4.3.15. Guidelines for Embedded Memory ECC Feature
4.3.16. FIFO Intel® FPGA IP Parameters
4.3.17. Reset Scheme
4.4.1. Release Information for FIFO2 Intel® FPGA IP
4.4.2. Configuration Methods
4.4.3. Fmax Target Measuring Methodology
4.4.4. Performance Considerations
4.4.5. FIFO2 Intel® FPGA IP Features
4.4.6. FIFO2 Intel® FPGA IP Parameters
4.4.7. FIFO2 Intel® FPGA IP Interface Signals
4.4.8. Reset and Clock Schemes
4.5.1. Release Information for Shift Register (RAM-based) Intel® FPGA IP
4.5.2. Shift Register (RAM-based) Intel® FPGA IP Features
4.5.3. Shift Register (RAM-based) Intel® FPGA IP General Description
4.5.4. Shift Register (RAM-based) Intel® FPGA IP Parameter Settings
4.5.5. Shift Register Ports and Parameters Setting
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4.3.14. Gray-Code Counter Transfer at the Clock Domain Crossing
This section describes the effect of the large skew between gray-code counter bits transfers at the clock domain crossing (CDC) with recommended solution. The gray-code counter is 1-bit transition occurs while other bits remain stable when transferring data from the write domain to the read domain and vice versa. If the destination domain latches on the data within the metastable range (violating setup or hold time), only 1 bit is uncertain and destination domain reads the counter value as either an old counter or a new counter. In this case, the DCFIFO still works, as long as the counter sequence is not corrupted.
The following section shows an example of how large skew between the gray-code counter bits can corrupt the counter sequence. Taking a counter width with 3-bit wide and assuming it is transferred from write clock domain to read clock domain. Assume all the counter bits have 0 delay relative to the destination clock, excluding the bit[0] that has delay of 1 clock period of source clock. That is, the skew of the counter bits will be 1 clock period of the source clock when they arrived at the destination registers.
The following shows the correct gray-code counter sequence:
000,
001,
011,
010,
110....
which then transfers the data to the read domain, and on to the destination bus registers.
Because of the skew for bit[0], the destination bus registers receive the following sequence:
000,
000,
011,
011,
110....
Because of the skew, a 2-bit transition occurs. This sequence is acceptable if the timing is met. If the 2-bit transition occurs and both bits violate timing, it may result in the counter bus settled at a future or previous counter value, which will corrupt the DCFIFO.
Therefore, the skew must be within a certain skew to ensure that the sequence is not corrupted.
Note: Use the report_max_skew and report_net_delay reports in the Timing Analyzer for timing verification if you use the User Configurable Timing Constraint. For Embedded Timing Constraint, use the skew_report.tcl to analyze the actual skew and required skew in your design.