Gradiente Expert DDPlus
Contents |
Description
The Expert DDPlus was the last MSX1 computer released by Gradiente. Compared with the Expert Plus, the built-in firmware has been removed and replaced by a 720KB 3,5" floppy disk drive.
And compared to Expert GPC-1, a reset button has been added, while RGB and bus expansion connectors have been removed. Main Ram slot changed from slot 2 to expanded slot 3.0.
| Brand | Gradiente |
| Model | Expert DDPlus |
| Year | 1989 |
| Region | Brazil |
| Launch price | |
| RAM | 64kB in slot 3-0 |
| VRAM | 16kB |
| Media | MSX cartridges, 2DD floppy disks |
| Video | Toshiba T6950, Texas Instruments TMS9918 compatible (Integrated in MSX-Engine T7937A) |
| Audio | Toshiba T7766A, General Instrument AY-3-8910 compatible (Integrated in MSX-Engine T7937A) |
| Chipset | Toshiba T7937A |
| Keyboard layout | QWERTY with a "ç" key + numeric keypad |
| Extras | 720kB 3,5" floppy disk drive, built-in speaker with volume control, reset button |
| Emulation | ROMs dumped and emulated |
Pictures
Specifications
The Gradiente Expert DDPlus is a MSX1. The Z80A, the VDP and the PSG are integrated in MSX-Engine T7937A.
The integrated VDP is the Toshiba T6950, which does not support some undocumented features of the Texas Instruments TMS9918, TMS9928 and TMS9929 VDP's.
The RAM is in slot 3-0, what has been source of trouble for some programs written for the two first Gradiente computers.
Slot Map
| Slot 0 | Slot 1 | Slot 2 | Slot 3-0 | Slot 3-1 | Slot 3-2 | Slot 3-3 | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Page C000h~FFFFh | Cartridge Slot 1 | Cartridge Slot 2 | 64kB RAM | |||||||
| Page 8000h~BFFFh | ||||||||||
| Page 4000h~7FFFh | Main-ROM | Disk ROM | ||||||||
| Page 0000h~3FFFh |
Connections
- RF output
- Video composite and analog sound output
- Monochromatic video output
- non-standard keyboard connector
- non-standard Data Recorder connector
- non-standard Centronics compatible Parallel port for a printer
- 2 general connectors (Joysticks, Mouse, Paddle controlers, etc)
- 2 cartridge slots
- 2 switched AC sockets