Olivetti · M
Olivetti M290 SP
1991 M290 with a 20 MHz 286, VLSI TOPCAT chipset and integrated WD90C11 video.
History
The preserved BIOS identifies itself as "M290 SP" and belongs to the same firmware family later used by the M300 BA013 boards and the PCS 11/33. Its processor, chipset, video and memory match the BA-08 board of the M290-25 described in the Olivetti service guide, but no primary source found so far ties the name M290 SP to the BA-08. It is a different model from the original M290, which uses another BIOS, and from the 1986 M28 SP.
Hardware
- Processor
- Intel 80286 20 MHz
- Memory
- 1, 3, 5, 9 or 17 MB (2 x 512 KB soldered + SIMM banks)
- Chipset
- VLSI TOPCAT 82C320/82C331
- Video
- Integrated Western Digital WD90C11 VGA
Catalogue classification
- Form factor
- Desktop
- Mobility
- Stationary
- Processor generation
- 80286 class
- Graphics standard
- VGA
Research
This page separates documented hardware facts, behavior observed in original firmware, and the current fidelity of BluMach emulation.
Sales and commercial configurations
Evidence: documented or confirmed hardware
- Commercial models
The service guide presents the M290-25 with the BA-08 board and 1 MB on board, expandable to 17 MB with a memory card, three 16-bit slots on the bus card and 40, 85 or 120 MB hard disks.
Architecture and memory
Evidence: documented or confirmed hardware
- CPU and bus
Intel 80286 at 20 MHz with a coprocessor socket. VLSI TOPCAT chipset: 82C320 (system controller) and 82C331 (bus controller). 8042 controller for the keyboard and PS/2 mouse.
- Memory
Banks 0 and 1 on the board: two soldered 256K × 18 devices, 512 KB each (1 MB). Banks 2 and 3 on the expansion card, each a pair of 1M × 9 (2 MB) or 4M × 9 (8 MB) SIMMs. 1 to 17 MB in total, 80 ns access.
- Video
Integrated VGA with a Western Digital WD90C11 (WD90C11A-LR in later revisions) and an ICS90C61 clock generator, with video memory sockets on the board. BluMach takes the character font from the firmware itself and sets the video chip's power-on state; that state has not been checked against a real board.
- Storage
National floppy controller with 1.2 MB (5.25") and 1.44 MB (3.5") drives, an IDE disk interface built from buffers and MSI logic, and serial and parallel ports in the 87C310. The BIOS 1.08 disk table has six types: 615/4/17, 980/5/17, 1014/9/18, 755/16/17, 762/8/39 and 873/13/36 (20 to 200 MB).
- Configuration
ROM Setup that opens by itself when the CMOS is invalid or the hardware changes. The extended Setup (EMS memory, shadowing, memory and bus speed, password) opens with Shift+Ctrl+Alt+Del.
BIOS and firmware
Evidence: observed in preserved firmware and boot testing
- Known revisions
One 128 KB image with Resident Diagnostics 1.08 and a ROM Setup in six languages. Copyright Olivetti 02/25/91. The BA-08 service guide lists revisions 1.04, 2.00 and 2.01 but not 1.08; according to the guide, 2.00 fixes random hangs, boot failures and A20 gate handling.
Emulation status
Evidence: current BluMach status; not necessarily a description of the original circuit
- Verified
BIOS 1.08 is identified and verified by hash. In BluMach it completes the Resident Diagnostics (CPU, ROM, refresh, parity, interrupts, DMA, keyboard, clock, protected mode and CMOS), initialises VGA video, detects the IDE disk and boots MS-DOS from the hard disk.
- Pending or approximate
Experimental emulation. The TOPCAT is a partial functional model with the BA-08 bank layout; the timer timing and the board line the BIOS reads with keyboard-controller commands 8Ah/8Bh are set to what the firmware checks, not measured on a real board. Setup, the other memory sizes and more software remain to be validated.
Sources
Preserved research material
Evidence: primary sources and research notes
- Published identity
- Link between the firmware name "M290 SP" and the M290-25/BA08 board: inferred from matching components, pending a primary source (service guide, board photo or EPROM label).