External Memory Interfaces Stratix® 10 FPGA IP User Guide

ID 683741
Date 11/28/2024
Public
Document Table of Contents

13.9.5.2.6. Address Pattern Examples - Advanced Mode

The examples in this topic include the generated address on both the Avalon® address (amm_address_0) and the memory address (mem_addr).

The difference in widths between amm_address_0 and mem_addr is based on the configured EMIF IP variant.

The following points apply to the examples that follow:

  • A value of X indicates that a register is not used, making its value irrelevant.
  • The address width (31) is the SYMBOL ADDRESS, as output from the traffic generator. In the design used for these examples, the AMM_WORD_ADDRESS_WIDTH is 26 bits. To account for this difference, the traffic generator shifts all addresses by the difference (5 bits). The examples below use this shifted address, but the external memory interface does not see this shift on its side of the ctrl_amm interface.
  • The provided waveform is only a snippet of the full instruction pattern, to demonstrate the write instructions and the corresponding addresses. Not all read blocks are shown, due to space restrictions.

The width of the Avalon® address is based on the following:

  • The data width on the memory side.
  • Whether a configured EMIF IP is quarter rate, half rate, or full rate.
  • Whether the memory interface is double data rate or quarter data rate.

Example 1: Random Address Mode

Consider the following instruction pattern:

TG_LOOP_COUNT=2 TG_WRITE_REPEAT_COUNT=1 TG_RW_GEN_IDLE_COUNT=2
TG_WRITE_COUNT=3 TG_READ_REPEAT_COUNT=1 TG_RW_GEN_LOOP_IDLE_COUNT=0
TG_READ_COUNT=3 TG_BURST_LENGTH=1
Table 359.  Address Pattern
   
Write Start Addresses:
TG_SEQ_START_ADDR_WR  =0x5a5a
TG_SEQ_START_ADDR_WR+1=0x0000
TG_SEQ_START_ADDR_WR+2=X
       …
TG_SEQ_START_ADDR_WR+11=X