|Also known as||Expert XP-800|
|Release date||December 1985|
|Operating system||MSX BASIC, MSX-DOS, CP/M|
|CPU||Zilog Z80A @ 3.58 MHz|
|Memory||64 KB–4096 KB (max.)|
|Removable storage||Cassette tape, cartridges, floppy discs|
The Expert (or Expert XP-800), made by Gradiente Eletrônica (to date best known as a game console and Hi-Fi equipment company) was the second and last MSX home computer launched in the Brazilian market, in the mid-1980s.
It was presented to the public at the 5th International Computing Fair, nicknamed "Informatica '85". The event took place at Anhembi Convention Center in the city of São Paulo from September 23 to 29, 1985. At the announcement, the computer was priced 65 ORTN s.
Its market release date was 1 December 1985, one week after Epcom's Hotbit, just in time for 1985's Christmas and with a massive media campaign on magazines, newspapers and TV. In the newspapers ads the initial offer price was Cr$ 4,640,000, or US$ 470 by the value at the time, or US$ 1,165 by the end of 2021.
The machine was a clone of the National CF-3000, with a computer case resembling a stereo system, a detached keyboard with a proprietary connector, no caps lock LED and no reset key, although the soft-reset could be achieved by pushing in either of the cartridge slot covers.
The two first versions had a graphite case and socketed chips, which caused a chronic problem: when the machine heated, the chips frequently pulled out and the system "froze". Also, the GPC-1, released in 1987, had a ROM slightly modified to solve an ASCII table compatibility issue with the other popular Brazilian MSX, Sharp's Hotbit.
Versions Plus/DD Plus
The last two versions had a black case and the problematic socketed chips were replaced by an ASIC. Nevertheless, the RAM was mapped to a secondary slot and, although it was straight by the MSX standards, caused a lot of crashes with programs who searched for memory in the wrong place. It did not contribute for the popularity of any of the Plus versions.
These machines used the MSX-Engine T7937A instead of the Z80A CPU of previous models.
|CPU||Zilog Z80A (XP-800 & GPC-1) @ 3.58 MHz|
MSX-Engine T7937A (Plus & DD Plus) @ 3.58 MHz
|Keyboard||mechanic, 89 keys (with 4 cursor keys), number pad|
|Display||text: 40×24 rows; graphics: 256×192 pixels, 16 colours, 32 sprites|
|Sound||General Instrument AY-3-8910 (PSG), 3 voices, white noise|
|Ports||2 joystick connectors, TV out, RGB monitor out, sound out, tape recorder connector, parallel port, 2 cartridge slots|
|Storage||tape recorder (1200/2400 bit/s) or one or two external floppy drives (51⁄4", 360 KB or 31⁄2", 720 KB)|
- DR-1 ("data-corder"): tape recorder
- JS-1: joystick
- MBW-12: 12" green CRT monochrome monitor
- TA-1: TV adapter
- TM-1: 1200/75 bit/s modem with a RS-232C port
- "Gradiente Expert XP-800". www.old-computers.com. Retrieved 2023-05-20.
- "5ª Sucesu e 18º Cong. Nacional da Informática". Museu de Eventos - Anhembi (in Portuguese). 2015-05-18. Retrieved 2023-05-20.
- "Uma Vitrine Renovada" (PDF). VEJA (in Portuguese). No. 891. October 2, 1985. pp. 88, 89.
- "Informática 85: o que há de novo no setor" (PDF). Micro Sistemas (in Portuguese). September 1985. p. 36.
- "BRENO ROSSI shop advertising". O Estado de S. Paulo (in Portuguese). No. 33.987. December 15, 1985. p. 24.
- "Gradiente Expert XP-800". MSX Resource Center. March 8, 2023.
- "Expert". Museu da Computação e Informática - MCI (in Portuguese). 2004.
- "GRADIENTE Expert Plus". OLD-COMPUTERS.COM.