1. This forum section is a read-only archive which contains old newsgroup posts. If you wish to post a query, please do so in one of our main forum sections (here). This way you will get a faster, better response from the members on Motherboard Point.

SDRAM configuration on SMDK2410X

Discussion in 'Embedded' started by Jeffrey Dutky, Jun 25, 2003.

  1. I'm trying to understand the Samsung SMDK2410X demo board (for the
    S3C2410 ARM microcontroller, see
    http://www.samsung.com/Products/Sem...ileASSP/MobileComputing/S3C2410X/S3C2410X.htm)
    but I can't seem to figure out how the SDRAM is configured.

    If I am reading the various SDRAM data sheets correctly, SDRAM chips
    must be configured, at startup, before use (after applying power and
    clock, issue a NOP condition for several hundred micro-seconds, then
    issue prechage commands to all banks, then issue several refresh
    cycles, finally issue a device configuration cycle to set the device
    configuration register contents). I had thought that the CPLD in the
    SMDK2410X schematic (U4) was responsible for configuring the SDRAMs at
    startup, but it doesn't appear to have control over most of the
    required signals (you need control over A0-A10, CAS, RAS, WE, and CS
    to configure the SDRAM, but the CPLD only has access to A0-A3), and
    appears to be used, mainly, to control the directional signal on the
    data bus transcievers.

    My question is: how are the SDRAMs configured on this board (or, in
    general, with the S3C2410X MCU)?

    1) Do the SDRAMs not really need any configuration (they start in an
    acceptable mode)?

    2) Does the S3C2410 issue the configuraiton signals after the MCUs
    internal memory controller is configured?

    3)Is there something else I am missing on the schematic?

    The MCU User's Manual is less than helpfull on this topic: very little
    expositive text, and what there is isn't all that well written. The
    memory controller section is even terser than the rest of the
    document.
     
    Jeffrey Dutky, Jun 25, 2003
    #1
    1. Advertisements

  2. See for example the U-Boot source code.


    Wolfgang Denk

    --
    Software Engineering: Embedded and Realtime Systems, Embedded Linux
    Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Web: www.denx.de
    Unix is like a toll road on which you have to stop every 50 feet to
    pay another nickel. But hey! You only feel 5 cents poorer each time.
    - Larry Wall in <>
     
    Wolfgang Denk, Jun 25, 2003
    #2
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.