Re: De2_tv

Altera_Forum · ‎09-13-2011

in example of DE2_TV. Mean of parameter in module Sdram control:

//////////// 100 MHz ///////////////

//*************************************************************************

parameter INIT_PER = 24000;

parameter REF_PER = 1024;

parameter SC_CL = 3;

parameter SC_RCD = 3;

parameter SC_RRD = 7;

parameter SC_PM = 1;

parameter SC_BL = 1;

parameter SDR_BL = (SC_PM == 1)? 3'b111 :

(SC_BL == 1)? 3'b000 :

(SC_BL == 2)? 3'b001 :

(SC_BL == 4)? 3'b010 :

3'b011 ;

parameter SDR_BT = 1'b0; // Sequential

// 1'b1: // Interteave

parameter SDR_CL = (SC_CL == 2)? 3'b10:

3'b11;

//*****************************************************************************************

please help me

Altera_Forum · ‎08-13-2013

nobody help me!! :(

Altera_Forum · ‎01-19-2018

SC_CL = CAS Latency

SC_RCD = Row Address to Column Address delay

SC_RRD = Row to Row activation delay

SC_PM = Page Mode

SC_BL = Burst Length

SDR_BT = Burst Type (sequential or Interleaved)

Altera_Forum · ‎01-25-2018

Also, the INIT_PER is initialization period. During initialization we first wait for 100us and then apply sequence of commands to initialize the SDRAM. The INIT_PER helps to keep track of where we are in the process and its value is decoded to decide which command to apply.

The REF_PER is counter used to decide when to issue auto-refresh command to the SDRAM.

For anyone requiring details, you must first understand the basic of an SDRAM. There are application notes that do that quite well and also carefully read the datasheet for the IS42S16320.

The following are a good start:

An introduction to SDRAM and memory controllers (Philips)

SDR SDRAM Controller (Reference Design RD1174) (Lattice Semiconductor)

SDR SDRAM Controller (Reference Design RD1010) (Lattice Semiconductor)

IS42S16320 Datasheet

Enjoy