Spectravideo svi 318-328

The ported games was just a matter of smaller changes of the VDP, PSG and PPI handling, some even worked with a patched MSX BIOS. SVI-328 and MSX BIOS/BASIC are almost identical. The major difference is the memory handling.

 
                    MSX      SVI-328
                    ---      -------
BIOS_OUTDO:         $0018    $0018
BIOS_WRTVDP:        $0047    $3536
BIOS_RDVRM:         $004a    $3734
BIOS_WRTVRM:        $004D    $372A
BIOS_INITXT:        $006c    $0047
BIOS_INIGRP:        $0072    $004A
BIOS_GICINI:        $0090    $4066
BIOS_WRTPSG:        $0093    $40B6
BIOS_TAPIN:         $00e4    $006C
BIOS_TAPOUT:        $00ed    $0075
BIOS_ISFLIO:        $014a    $68C2
etc.

PRN_WRITE_DATA:     $91      $10
PRN_WRITE_STROBE:   $90      $11
PRN_READ_STATUS:    $90      $12

VDP_WRITE_DATA:     $98      $80
VDP_WRITE_LATCH:    $99      $81
VDP_READ_DATA:      $98      $84
VDP_READ_STATUS:    $99      $85

PSG_WRITE_LATCH:    $a0      $88
PSG_WRITE_DATA:     $a1      $8C
PSG_READ_DATA:      $a2      $90

PPI_READ_PORTA:     $a8      $98
PPI_READ_PORTB:     $a9      $99
PPI_WRITE_PORTC:    $aa      $96
PPI_READ_PORTC:     $aa      $9A
PPI_WRITE_CTRL:     $ab      $97

There existed also a hardware adapter, SVI-606. The adapter was connected to the SVI-328 expansion slot and had an MSX cartridge slot, cassette port, 2 joysticks and small keyboard. However it was too expensive and wasn’t that compatible.
http://www.saunalahti.fi/hifi4/svi/new/SVI606.jpg

The SVI-328 with the Super Expander was also a competitive CP/M system.
http://www.old-computers.com/museum/computer.asp?st=1&c=228

manuel: You can also try SDLMESS and use cartridge or disk for loading Frantic Freddy.

The SVI-328 memory banks are 32KB each instead of 16KB and have no sub slots. If we translate this into MSX language you would get:

       SLOT 0    SLOT 1    SLOT 2    SLOT 3
FFFF +---------+---------+---------+---------+
     | BANK 02 | BANK 12 | BANK 22 | BANK 32 | PAGE 3
     |   RAM   |ROM CART |   RAM   |   RAM   |
8000 |00000000 |00000000 |10100000 |11110000 | PAGE 2
     +---------+---------+---------+---------+
7FFF | BANK 01 | BANK 11 | BANK 21 | BANK 31 | PAGE 1
     |ROM BASIC|ROM CART |   RAM   |   RAM   |
     |00000000 |00000101 |00001010 |00001111 | PAGE 0
0000 +---------+---------+---------+---------+

Take a look at the "Spectravideo Assembly Programming" manual at Roger Samdal's page, it's a valuable resource although most parts are written in Swedish.
http://www.samdal.com/svdocuments.htm

Here's a link to a SVI-328 and SVI-728 symbol files that could be used for reference and debugging with for example blueMSX. The SVI-328 naming are all in MSX format, therefore you could find a lot of resources.
http://www.bluemsx.com/dev_download/svi328/SymbolSvi328Msx.zip

Have you found the Porting MSX games to SVI-3x8 & vice-versa thread?