Aitech S703

Introduction

Aitech’s S703 MIL-STD-1553B PMC features one BU61688 Mini-Advanced Communication Engine or a BU61582 SpaceACE hybrid by DDC. Each terminal provides dual transceiver and encoder/decoder, complete MIL-STD-1553B protocol, 16k words of shared RAM, and memory management logic for all three modes (BC/RT/MT). Background Mode Operation prevents inadvertent access to the card during power-on self-test. On-board Interrupt Mask and Interrupt Status Registers support flexible operation for both interrupt and polling applications.

The memory management scheme for RT mode provides an option for separation of broadcast data plus a circular buffer option for individual RT sub-addresses to off-load the demands on the PC host processor.

The S703’s PCI interface provides bridging capabilities between the carrier board PCI bus and the local MIL-STD-1553B controller bus. The Bridge supports a 32-bit wide PCI bus clocked at 33.333 MHz. This high bandwidth path can achieve data transfer rates of 132 MB/s taking advantage of the 32-bit data width required. The PCI Local Bus is compliant to Rev. 2.1 specifications.

The S703 interface to the MIL-STD-1553B bus is either for transformer (long stub) or direct (short stub) coupling. Each S703 terminal/channel pair can be switched to use either transformer or direct coupling according to the factory installed configuration (transformer coupling by default).

Both, transformer and direct-coupling configurations require the use of an isolation transformer located on the S703 PMC. For the (long stub) transformer-coupled configuration, a second transformer (referred to as a bus-coupling transformer) is required, in accordance with MIL-STD-1553B.

In addition, both coupling configurations require an isolation resistor to be placed in series with each leg of the transformer connecting to the MIL-STD-1553B bus. This design protects the bus against short circuit conditions in the transformers, stubs, or terminal components.

For more details, refer to datasheet.