VMEbus 32 MB Memory Expansion Module, supporting SRAM, EPROM or FLASH with battery backup & Watch-dog.

Extensive Software Support

BSPs for the leading real-time operating systems - UNIX, SUN, WIN, etc.


The CM-MEM-40 is a 32 bit general purpose VMEbus Memory Expansion Board that incorporates features demanded in military & industrial applications.

CM-MEM-40 - Memory Expansion

Maximum on-board capacity is 32 MB, distributed in 16 banks, each one populated with four 32 pin JEDEC devices of 512KB of capacity.

Memory chips of SRAM, EPROM or FLASH may be installed in a flexible way, supporting all standard JEDEC chips.

The metallic layer within the PCB benefits heat dissipation & uniform component temperatures, thus increasing component longevity & module MTBF.

CM-MEM-40 - Memory Expansion

Jumpers allow mapping the board in any of the 128 memory blocks, 32 MB size, available in the Extended A32/D32 addressing range. On-board programming is carried out with +5VDC only.

Military versions with thermal overlay greatly improve capability to withstand shock & vibration.

The CM-MEM-40 32 MB SRAM version (CM-MEM-40/S) incorporates a watch-dog & stand-by rechargeable battery, allowing for use as a solid state hard disk (RAM disk).

CM-MEM-40 - ATR Chassis

All versions are compatible at the function level, Industrial versions allow low cost software development.


CM-MEM-40/C - Commercial

C: Commercial range >> Implements low cost Commercial plastic IC's rated for 0 to +70°C. Continuous board operation from 0 to +60°C. Class II industrial quality connectors. Storage from -10 to +85°C.


CM-MEM-40/I - Industrial

I: Industrial range >> Manufactured with Industrial range plastic or ceramic IC's rated for -25 (-40) to +85°C. Continuous module operation from -20 to +75°C. Class II industrial quality connectors. Storage from -40 to +100°C.


CM-MEM-40/R+ - Military Rugged

R+: Military Rugged+ range >> Implements ceramic IC's rated from -55 to +125°C. Class I MIL-C-55302 connectors. Conduction cooled PCB with thermal overlay. Operation from -40 to +85°C. Storage from -55 to +125°C.

Military 883

CM-MEM-40/883 - Military 883

883: Military 883 range >> Manufactured with conduction cooled PCB & MIL-STD-883 B/C military ceramic parts (-55 to +125°C). Class I MIL-C-55302 connectors. Operation from -50 to +90°C. Storage from -55 to +125°C.

MIL-STD Components

  • MIL-STD-810E Temperature (Methods 501.3 & 502.3)
  • -55°C to +125°C ceramic military ICs
  • Military Class V Printed Circuit Board
  • MIL-C-55302 Class I Connectors
  • High Stability MIL-STD-883 SRAMs.
  • MIL-STD-883 TTL chips.
  • MIL-E-5400 Class 1B (Temp. & Altitude)
  • MIL-STD-810E Shock & Vibration (Methods 516.4 & 514.4)
  • No PCB tracks in external layers
  • MIL-STD-810E Saline Fog & Dust (Methods 507.3 & 509.3)

CM-MEM-40 Specifications

  • Capacity: Up to 32 MB in steps of 2MB. The board incorporates 16 independent memory banks of 2MB & 32 bit wide. A bank is composed by 4 JEDEC chips of 512 KB capacity.
  • SRAM Memory: The CM-MEM-40/S allows up to 32MB of SRAM. Accepted chips are rated from 35 to 12 ns of access time. The total amount of SRAM can operate in "stand-by".
  • Flash Memory: Up to 32 MB. The board supports new generation Am-29F040 devices requiring only +5V for its on-board erase or programming.
  • EPROM Memory: Up to 32 MB. To allow external programming the board offers 64 sockets for 27C4000 devices.
  • VME Decoder: Allows to map the board in the VME range in a flexible manner. There are 128 positions, 32 MB size each.
  • VME Access Time: The board responds to VMEbus data transfers in 100 ns (0 wait state).
  • Wait-state Generator: Equates the VMEbus access time versus the speed of installed devices. A jumper allows 0, 1, 2 or 3 wait states for chips from 35 to 120 ns.
  • Back-up Battery: A Ni/Cd rechargeable battery (100mA/h) supplies the stand-by voltage.
  • Watch-dog: A MAX-690 monitors the +5VDC and administrates the back-up battery.
  • VMEbus Interface: According the IEEE 1014 rev. C. The board responds to VMEbus Extended transfers type A32/D32/D16/D8(EO).
  • Front panel LED: 1 LED that indicates when module is active.
  • VME Addressing: Two jumper blocks provide 256 mapping options in the A24 range.
  • Power consumption: +5VDC @ 600 mA (3 Watts).
  • Weight (grams): C & I ver.: 405gr. | R+ & 883 ver.: 510gr.
  • Mechanical size: Single slot 6U (233x160 mm).
  • Mechanical format:
    • CM-MEM-40/A: IEC-297 mechanics for 19 inch racks with I/O on front panel.
    • CM-MEM-40/B: Military IEEE P1101 wedgelock mechanics for ATR enclosures.
  • Humidity: Up to 95% RH non-condensing.
  • Altitude: Sea level up to 15 Km (50,000 ft.).

CM-MEM-40 Features

  • On-board memory capacity up to 32 MB.
  • Flexible memory chip insertion; SRAM, EPROM or FLASH.
  • 16 memory banks with four 32 pin JEDEC devices of 512KB capacity.
  • Fast CMOS low heat design (3 Watts).
  • On-board programming with +5VDC only.
  • Extremely fast access time.
  • Supports all standard JEDEC chips.
  • Variable wait-state generator.
  • Module mapping to any 128 memory blocks, 32 MB size.
  • Watch-dog timer & Stand-by rechargeable battery incorporated.
  • Module assert DTRACK* in 100ns.
  • Up to 64 chips in CM-MEM-40/F versions.
  • EPROM type 27C400 supported.
  • CM-MEM-40/S/F allows FLASH & SRAM combinations up to 16 MB.
  • Commercial, Industrial, Rugged & 883 versions.
  • IEC-297 mechanics with I/O via front panel and military P1101.2 wedge-lock mechanics.
  • Conduction cooled PCB with thermal overlay in MIL-Rugged and 883 versions.
  • Extensive software support.
  • Excellent price/performance ratio.
  • Low power CMOS design (3 Watts).
  • Two year guarantee.

CM-MEM-40 Ordering

Ordering Example: CM-MEM-40 /V /T /M

V (Board Version)
S1: Memory expansion with 8 MB SRAM. Battery & Watch-dog.
S2: Memory expansion with 16 MB SRAM. Battery & Watch-dog.
S3: Memory expansion with 32 MB SRAM. Battery & Watch-dog.
F1: Memory expansion with 8 MB FLASH. Battery & Watch-dog.
F2: Memory expansion with 16 MB FLASH. Battery & Watch-dog.
F3: Memory expansion with 32 MB FLASH. Battery & Watch-dog.
SF: Memory expansion with 8 MB SRAM + 8 MB FLASH. Battery & Watch-dog.
SF: Memory expansion with 16 MB SRAM + 16 MB FLASH. Battery & Watch-dog

T (Board Temperature Range)
C: Commercial. Fiberglass PCB only.
I: Industrial. Fiberglass PCB only.
R+: Military Rugged+. Conduction cooled PCB only.
883: Military 883. Conduction cooled PCB only.

M (PCB Mechanical Version)
A: IEC-297 Mechanics with front panel I/O connectors.
B: P1101.2 Military mechanics, dummy front panel & wedge-locks.

Ordering Example

Part Number Example: CM-MEM-40/1/R+/B
- Memory expansion board with 8 MB SRAM. Battery & Watch-dog.
- Military Rugged+ range (-40 to +85°C operating).
- IEEE P1101.2 Military mechanics with wedge-locks.


LEVEL 1, CM-MEM-40 MAP: User´s manual. Module hardware functional description oriented toward software development.

LEVEL 2, CM-MEM-40 MMT: Maintenance manual with BIT scope, test point wave forms. logic analyzerdiagrams, etc.

LEVEL 3, CM-MEM-40 NAT: Maintenance manual according to NATO forces. Includes the above manuals plus mechanical & electrical schematics, NATO list part number, extended functional description, maintenance & calibration procedures for in-service equipment.

Software Support

Wind River Systems VxWorks Tornado: The CM-MEM-40 is supported by VxWorks Tornado & is ideal for developing real time software under UNIX environments. A complete "C" language driver in source code is available at low cost. Drivers include a floppy-disk & user's manual.

Microware Systems OS-9: Drivers for the real time OS-9 Operating System are available in "C" language. This driver is supplied with user's manual & source code floppy-disk.

Microtec Research MCC-68K Drivers: A "C" language source code driver written for the MCC-68K cross-compiler from Microtec Research. This low cost option is intended for using a PC as host.

* NOTE - Drivers for other leading operating systems can be optionally supplied under request.