The new hardware from Leonardo Padial is a high reliability 4MBytes dinamic RAM cartridge in an small size board (6x6,5cm) suitable for Sony, Konami, Pazos or Sunrise cartridge cases (7x11cm). This memory board supports Z80 at 14.3 Mhz too. After power on, the cartridge behaves as an standard 4MBytes RAM expansion but it can works as a single MegaRAM of 2MBytes expansion (non expanded slot). The .ROM files can be loaded from DOS or BASIC without any conversion (.ROM file is loaded into upper 2MBytes and executed with a software reset jumping to the &h0000 position). The main features are:

  • 4MBytes of RAM with standard mapper or 2MBytes of MegaRAM (ASCII, Konami an others mappers).
  • After power on, the cartridge behaves as an standard 4MBytes RAM (pages 0-255).
  • 2MBytes of the 4MBytes (pages 128-255) are converted into read only pages (0-127), allowing to load from Basic.
  • The transition from 4MBytes to 2MBytes is done through the transition register and a SW reset.
  • Reversible transition RAM <-> MegaRAM.
  • Transition register --> address &H54.
    Bit0=0 selects 4MBytes.
    Bit0=1 selects 2MBytes.
    Bit1=0 selects pages of 16K.
    Bit1=1 selects pages of 8K.
  • For the 8K universal mapper registers, four pre-registers are used, addresses &H55/&H56/&H57/&H58. This allows to pre-load any mapper register value. Example: &H40,&H60,&H80,&HA0. It is also allowed to load initial page values directly (addresses &H59/&H5A/&H5B/&H5C).
  • For the 16K mapper registers, no pre-registers are used but two decoded registers in addresses &H60xx/&H70xx. It also allows initial page values to load directly (addresses &H5A/&H5B).
  • The MSX-DOS tool works as follows:

    A>LPE4FMB FILE.ROM /Mapper /Slot

    Mappers:

    • /4 Konami4
    • /5 Konami5
    • /6 ASCII16
    • /8 ASCII8

    Slot (optional). This value indicates the LPE4FMB slot. Examples:

    • /S1-3: It loads the file (Mega)ROM in slot 1-3.
    • /S2: It loads the file (Mega)ROM in slot 2.

The price of this new hardware is 85€. For further information, please visit the Leonardo Padial's web site.

Relevant link:Leonardo Padial's RAM and MegaRam Memory Expansions

Comments (2)

By flyguille

Prophet (3029)

flyguille's picture

11-04-2015, 17:16

if it is a cartridge meant to load roms as an extra feature, why it don't emulate the SCC aswell?, it would be cool.

By fernando.collazo.5682

Master (236)

fernando.collazo.5682's picture

17-04-2015, 04:51

Can I use execrom to load megarom games in megaram mode?

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