Mcontr

From ElphelWiki
Jump to: navigation, search

Description

FPGA module that controls reads and writes between FPGA and DDR SDRAM (boards 10353 & 10359).

Bank interleaving

  • Taken from Theora's code.
  • Banks addresses (SDA[14:13]) and order used in a single memory access: 00&10, 11&01, 10&00, 01&11.
  • Both banks are opened in the beginning of the sequence.
  • Write/read sequence is divided by 2 and all column addresses are the same.
  • Row address of the second bank in a sequence is the first bank's + 1.


Programmable SDRAM sequence

Programmable:

  • sequence length
  • tile length in column(x4 banks)
  • tile width in rows
  • address shift in a column for a new tile
  • address shift in a row for a new tile
  • maximum number of tiles in a column
  • maximum number of tiles in a row


Reg Name Description
0x0c ch0x channel 0 tile length
0x14 ch0y channel 0 tile width
0x0d ch1x channel 1 tile length
0x15 ch1y channel 1 tile width

TODO

  • bank interleaving
  • run-time programmable SDRAM sequencing