<?xml version="1.0" ?>

<!-- TODO: Dump ROMs from a 8255 and verify that they are the same as 8250. -->

<!DOCTYPE msxconfig SYSTEM 'msxconfig2.dtd'>

<msxconfig>

  <info>

    <manufacturer>Philips</manufacturer>

    <code>NMS 8255</code>

    <release_year>1986</release_year>

    <description>European desktop MSX2 (as NMS 8250) with two double sided disk drives.</description>

    <type>MSX2</type>

    <region>eu</region>

  </info>

  <MapperReadBackBits>largest</MapperReadBackBits>

  <CassettePort/>

  <devices>

    <PPI id="ppi">

      <sound>

        <volume>16000</volume>

      </sound>

      <io base="0xA8" num="8"/> <!-- S-3527 mirrors -->

      <keyboard_type>int</keyboard_type>

      <has_keypad>true</has_keypad>

      <key_ghosting_sgc_protected>true</key_ghosting_sgc_protected>

      <code_kana_locks>false</code_kana_locks>

      <graph_locks>false</graph_locks>

    </PPI>

    <VDP id="VDP">

      <version>V9938</version>

      <vram>128</vram>

      <io base="0x98" num="8" type="O"/> <!-- S-3527 mirrors -->

      <io base="0x98" num="8" type="I"/> <!-- S-3527 mirrors -->

    </VDP>

    <PSG id="PSG">

      <type>YM2149</type> <!-- in S-3527 MSX-ENGINE -->

      <sound>

        <volume>21000</volume>

      </sound>

      <io base="0xA0" num="8" type="IO"/> <!-- S-3527 mirrors -->

      <ignorePortDirections>true</ignorePortDirections> <!-- not sure, but guess based on use of Engine IC -->

    </PSG>

    <RTC id="Real time clock">

      <sramname>nms_8255.cmos</sramname>

      <io base="0xB4" num="2" type="O"/>

      <io base="0xB5" num="1" type="I"/>

    </RTC>

    <PrinterPort id="Printer Port">

      <io base="0x90" num="8" type="IO"/> <!-- S-3527 mirrors -->

      <status_readable_on_all_ports>true</status_readable_on_all_ports> <!-- S-3527 property -->

      <unused_bits>0x00</unused_bits> <!-- as measured on one NMS 8250 -->

    </PrinterPort>

    <primary slot="0">

      <ROM id="MSX BIOS with BASIC ROM">

        <rom>

          <filename>nms8250_basic-bios2.rom</filename>

          <sha1>6103b39f1e38d1aa2d84b1c3219c44f1abb5436e</sha1>

        </rom>

        <mem base="0x0000" size="0x8000"/>

      </ROM>

    </primary>

    <primary external="true" slot="1"/>

    <primary external="true" slot="2"/>

    <primary slot="3">

      <secondary slot="0">

        <ROM id="MSX Sub ROM">

          <mem base="0x0000" size="0x10000"/> <!-- it is mirrored all over the slot -->

          <rom>

            <filename>nms8250_msx2sub.rom</filename>

            <sha1>5c1f9c7fb655e43d38e5dd1fcc6b942b2ff68b02</sha1>

          </rom>

        </ROM>

      </secondary>

      <secondary slot="1"/>

      <secondary slot="2">

        <MemoryMapper id="Main RAM">

          <size>128</size>

          <initialContent encoding="gz-base64">eNpj+M8wouEI9z4DAJBx/wE=</initialContent> <!-- (chr(0) + chr(255)) * 128 + (chr(255)+ chr(0)) * 128) -->

          <mem base="0x0000" size="0x10000"/>

        </MemoryMapper>

      </secondary>

      <secondary slot="3">

        <WD2793 id="Memory Mapped FDC">

          <connectionstyle>Philips</connectionstyle>

          <mem base="0x0000" size="0x10000"/>

          <!-- Verified on a real 8250 and 8280: FDC registers are visible

               in all 4 pages, rom only in page 1. This is handled internally

               in the WD2793 device -->

          <rom_visibility base="0x4000" size="0x4000"/> <!-- ROM only visible in page 1 -->

          <drives>2</drives>

          <rom>

            <filename>nms8250_disk.rom</filename>

            <sha1>dab3e6f36843392665b71b04178aadd8762c6589</sha1>

            <sha1>c3efedda7ab947a06d9345f7b8261076fa7ceeef</sha1>

          </rom>

        </WD2793>

      </secondary>

    </primary>

  </devices>

</msxconfig>