The Emerson/Motorola MVME166-11A is a single-board computer built on the Motorola MC68040 microprocessor for industrial and embedded control systems. Operating at 33 MHz with integrated 8KB cache, MMU, and FPU, this VMEbus-based platform delivers deterministic computing in harsh environments. The board combines ECC-protected DRAM, battery-backed SRAM, and Flash memory with a full suite of I/O interfaces including VMEbus master/slave capability, four TTL serial ports, SCSI, Ethernet, and parallel printer connectivity. Onboard ASICs (VMEchip2, VSBchip2, PCCchip2, and MCECC) handle VMEbus arbitration, VSB interfacing, peripheral control, and memory protection. Status LEDs monitor system health across VME, VSB, LAN, SCSI, and power rails, while hardware timers and watchdog functions enable real-time control applications.
## Technical Specifications
**Processor & Memory**
• Motorola MC68040 at 33 MHz with 8KB cache, MMU, FPU
• 4 MB ECC-protected DRAM (configurable to 256 MB on some variants)
• 128 KB SRAM with battery backup
• 8 KB SRAM with battery backup and time-of-day clock
• 1 MB Flash memory with download EPROM
**Interfaces**
• VMEbus: A16/A24/A32/D8/D16/D32/D64 master/slave, system controller capable
• VSB interface via VSBchip2 ASIC (P2 connector rows A and C)
• Four serial ports with CD2401 controller, TTL interface, 110 to 38.4 kbaud configurable for EIA-232-D
• SCSI bus interface with 32-bit local burst DMA via 68-pin connector
• Ethernet transceiver via PCCchip2 ASIC
• 8-bit bidirectional Centronics-compatible printer port
• Two high-density shielded front panel I/O connectors
**Onboard Features**
• Four 32-bit tick timers for periodic interrupts
• Watchdog timer
• Ten status LEDs (FAIL, STAT, RUN, SCON, LAN, RPWR, SCSI, VME, TPWR, VSB)
• RESET and ABORT switches
• BootBug monitor in EPROM for code download and Flash reprogramming
## Key Features
VMEbus system controller architecture with integrated DMA, interrupt handling, and bus arbitration. Memory subsystem features ECC protection and battery-backed retention for critical data. Multiple serial ports support legacy industrial protocols. SCSI and Ethernet expansion enable networked I/O and mass storage integration.
## Typical Applications
Process control, test automation, data acquisition, VMEbus crate controllers, and real-time embedded systems requiring long-term supply availability and industrial temperature operation.
## Compatibility & Integration
Direct VMEbus integration; VSB local bus for high-speed peripheral attachment. BootBug firmware simplifies development and field updates via Flash reprogramming.


















