Spectravideo SVI 728

Spectravideo SVI-728

The Spectravideo SVI-728 is an MSX1 computer that uses a TMS9129 VDP and is compatible with the PICO9918. For general MSX information, see the MSX page.

About the Spectravideo SVI-728

The SVI-728 was released by Spectravideo in 1985 as their first MSX-compatible computer, following the earlier (pre-standard) SVI-318 and SVI-328. It features a Z80A CPU, 64KB RAM, 32KB ROM, and a TMS9129 VDP for PAL regions. The machine was sold primarily in European and Asian markets.

Installation

Important: The SVI-728 uses a TMS9129 VDP. The PICO9918 must be configured for TMS9129 device mode before installation, otherwise the CPUCLK signal on pin 37 will not be driven correctly and the machine will not boot. Use the web configurator to apply the device mode setting before fitting the PICO9918.

1. Configure the PICO9918 for TMS9129 device mode using the web configurator
2. Power off and open the SVI-728
3. Locate the TMS9129 VDP (40-pin DIP package)
4. Carefully remove the existing VDP from its socket (if socketed) or desolder it and fit a 40-pin DIP socket
5. Insert the PICO9918 in the same orientation (pin 1 aligned)
6. Connect the VGA dongle, Digital AV Dongle, or SCART cable
7. Close the computer and power on

Configurator

As an MSX computer, the SVI-728 has full configurator support using the MSX configurator ROMs. Both ASCII16 and Konami mapper variants are available. See MSX Configurator and Configurator for details.

Technical Notes

• The SVI-728 uses PAL video timing with a TMS9129 VDP
• The TMS9129 provides CPUCLK on pin 37 (not pin 38 as on the TMS9918A) — this is why the device mode must be set correctly before installation
• See MSX Technical Notes for general MSX VDP technical details