diff --git a/User-Documentation.md b/User-Documentation.md index e674986..f9d004c 100644 --- a/User-Documentation.md +++ b/User-Documentation.md @@ -16,14 +16,14 @@ The recommended way to instantiate this IP is to use the top module `rtl/ddr3_to | BA_BITS | width of bank address. Use chapter _2.11 DDR3 SDRAM Addressing_ from [JEDEC DDR3 doc (page 15)](https://www.jedec.org/sites/default/files/docs/JESD79-3F.pdf) as a guide. Usual value is `3`. | | DQ_BITS | device width. Use chapter _2.11 DDR3 SDRAM Addressing_ from [JEDEC DDR3 doc (page 15)](https://www.jedec.org/sites/default/files/docs/JESD79-3F.pdf) as a guide. Possible values are `4`, `8`, or `16`. [1] | | LANES | number of DDR3 device to be controlled. This depends on the DDR3 module used. [1] | -| AUX_WIDTH | width of auxiliary line. Value must be >= 4. | +| AUX_WIDTH | width of auxiliary line. Value must be >= 4. [2] | | WB2_ADDR_BITS | width of 2nd wishbone address bus for debugging (only relevant if SECOND_WISHBONE = 1). | | WB2_DATA_BITS | width of 2nd wishbone data bus for debugging (only relevant if SECOND_WISHBONE = 1). | | OPT_LOWPOWER | _has no effect yet_ | | OPT_BUS_ABORT | _has no effect yet_ | | MICRON_SIM | set to 1 if used in Micron DDR3 model to shorten power-on sequence, otherwise 0. | | TEST_DATAMASK | set to 1 if datamask needs to be tested on the calibration sequence, otherwise 0. | -| ODELAY_SUPPORTED | set to 1 if ODELAYE2 primitive is supported by the FPGA, otherwise 0. [2]| +| ODELAY_SUPPORTED | set to 1 if ODELAYE2 primitive is supported by the FPGA, otherwise 0. [3]| | SECOND_WISHBONE | set to 1 if 2nd wishbone for debugging is needed , otherwise 0.| @@ -60,7 +60,8 @@ Below are the **auxiliary ports** associated with the main wishbone. This is not **Note:** [1]: For x16 DDR3 like in Arty S7, use `DQ_BITS` of 8 and `LANES` of 2. -[2]: ODELAYE2 is supported if DDR3 device is connected to an HP (High-Powered) bank of FPGA. HR (High-Rank) bank does not support ODELAYE2 as based on [UG471 7-Series Select Guide (page 134)](https://docs.xilinx.com/v/u/en-US/ug471_7Series_SelectIO). +[2]: The auxiliary line is intended for AXI-interface compatibility but is also utilized in the reset sequence, which is the origin of the minimum required width of 4. +[3]: ODELAYE2 is supported if DDR3 device is connected to an HP (High-Powered) bank of FPGA. HR (High-Rank) bank does not support ODELAYE2 as based on [UG471 7-Series Select Guide (page 134)](https://docs.xilinx.com/v/u/en-US/ug471_7Series_SelectIO). # Verify Design \ No newline at end of file