Tahoma / IKON 10089 DR11-W VMEbus Emulator

The Tahoma/IKON 10089 DR11-W VMEbus Emulator is a high-speed parallel Direct Memory Access (DMA) interface that provides full emulation of the Digital Equipment Corporation DR11-W for VMEbus environments. It enables inter-processor communication and connects VMEbus systems to peripheral devices, network nodes, mainframe channel interfaces, and workstations equipped with DR11-W interfaces. The emulator supports A32 addressing and D32 data transfer with high-speed FIFO buffering.

– Technical Specifications

The 10089 delivers complete DMA external cycles in approximately 800 ns under medium cycle mode conditions (assuming 200 ns memory and fast arbitrator), with approximately 450 ns allocated to VMEbus control. Output settling time ranges from 160 ns (short) to 225 ns (medium) to 350 ns (long), with END CYCLE H pulse width at 125 ns. Input de-skew timing extends from 110 ns (short) to 175 ns (medium) to 300 ns (long).

External signals are terminated with 180 Ω to VCC and 390 Ω to ground. Signal transmission and reception utilize DS8838-type transceivers with 70 mA sink capability and low-voltage hysteresis. All DR11-W I/O modes are supported, including control of bus address and range counter incrementing.

– Key Features

• A32/D32 addressing and data transfer capability
• High-speed parallel DMA interface with FIFO buffering
• VMEbus master/slave architecture support
• Asynchronous bus with variable-speed handshaking protocol
• Non-multiplexed bus design
• 16 to 32-bit addressing range and 8 to 32-bit data path widths
• VMEbus bandwidth up to 40 Mbyte/second
• VME64x Extensions support with up to 160 Mbyte/second bandwidth
• ACLO FNCT2 HI INIT H and GO H pulse width: 250 ns

– Compatibility & Integration

The emulator links VAX, LSI-11, PDP-11, Gould/Sel, Data General, Harris, and IBM systems. It integrates with Multibus, VERSAbus, VMEbus, and Prime architectures using IKON’s DR11-W emulator family. Full DEC DR11-W emulation enables compatibility with any peripheral device, graphics equipment, network node, mainframe channel interface, or workstation supporting the original DR11-W interface specification.