MM-6230D

A High Speed, 16MB, VMEbus Compatible DRAM Memory
Features
Capacity: 4, 8, 12, 16M
Cycle Time: 240 nsec
Read/Write Access 175 nsec/50 nsec (Fast Write)
VMEbus-compatible with A32/A24, D32/D16/D8 (UAT)
Block mode transfers for sequential access (BLT)
Parity generation and checking for error detection on each byte
Module Selection on 64KB boundaries, switch-selectable upper and lower limits in each of the 16MB banks
Six-bit address modifiers support user and supervisory modes
Description

The MM-6230D main board is a high density memory module that provides 4M, 8M, 12M, or 16MB. The memory module is completely compatible with the VMEbus and supports A32/A24, D32/D16/D8, byte, word, long word, unaligned bus transfer (UAT) and Fast-Write cycles. It also supports sequential access block mode transfers (BLT) of 256 bytes. Module selection is on 64KB boundaries, whose upper and lower limits are switch-selectable. To simplify reprogramming, address modifiers are programmed and decoded in a socketed IFL. Parity generation and checking are provided for each byte. Parity status is stored and transmitted via BERR* signal. If the BERR* signal is asserted, the DTACK* signal is inhibited during memory read operations. Reliability is ensured by burn-in and running memory diagnostics that check operation for 48 hours while temperature-cycling boards from 0 to 60°C.

MM-6230D Specifications
bullet

Capacity : 4M, 8M, 12M, 16MB with parity
bullet

Cycle Time : 240 nsec for Read or Write
bullet

Access Time : Read = 175 nsec, Write = 50 nsec (Fast Write)
bullet

Address : A32/A24 address bits
bullet

Data In/Data Out : D32/D16/D8 bits (UAT)
bullet

Sequential Access : Block mode transfers within a 256 byte boundary (BLT)
bullet

Address Modifiers : 6 bits, decoded by a socketed IFL to support user and supervisory modes
bullet

Parity : Byte-wide parity generation and checking; parity output stored and transmitted via BERR*

bullet

Interface : VMEbus-compatible (48 mA drivers)
bullet

Modes of Operation : Read, Write, Read-modify-Write, and refresh
bullet

Refresh : Hidden refresh, 250 nsec cycle every 15 usec
bullet

Memory Selection : Switch-selectable upper and lower limits for 64KB boundaries
bullet

Operating Temperature : 0 to 60°C
bullet

Storage Temperature : -40 to +85°C
bullet

Relative Humidity : Up to 95% without condensation
bullet

Power Requirements : +5V (Fully-populated), Standby 2.7A, Operate 2.9A