VMIVME-5576 Fiber Optic Reflective Memory with Interrupts Product Overview
Product Overview
-The Reflective Memory concept provides a very fast and efficient way to share data between distributed computer systems.
VMIC’s VMIVME-5576 Reflective Memory interface allows data to be shared between up
to 256 independent systems (nodes) at rates of up to 6.2 Mbyte/s. Each Reflective Memory board can be configured with up to 256 nodes.
Each Reflective Memory board can be configured with 256 Kbytes to 1 Mbyte of on-board SRAM.
local SRAM allows fast reads of stored data.
Write data is stored in the local SRAM and broadcast to other Reflective Memory nodes via a high-speed fiber optic data path.
Data transfers between nodes are software transparent, so there is no I/O overhead.
Transmit and receive FIFOs buffer data during peak data rates to optimize
CPU and bus performance and maintain high data throughput.
Reflective memory also allows interrupts to one or more nodes by writing to byte registers.
These interrupt (tertiary, user-definable) signals can be used to synchronize system processes or to follow any previous data.
Interrupts always follow the data to ensure that the data is received before the interrupt is acknowledged.
The VMIVME-5576 does not need to be initialized unless interrupts are used.
If interrupts are used, vectors and interrupt levels must be written to on-board registers and interrupts must be set.
Each node on the system has a unique identification number between 0 and 255.
The node number is determined by placing jumpers on the board during hardware system integration.
The node number can be read by software by accessing the on-board registers.
In some applications, the node number helps determine the function of the node.