XYCOM  XVME-103 is a versatile memory expansion module designed for the VMEbus architecture. It features eight 32-pin JEDEC sockets arranged in two independent banks, supporting up to 4 MB of RAM, 8 MB of EPROM, or 4 MB of Flash/EEPROM. With an onboard battery backup circuit for CMOS RAM protection during power failures, it is IEEE 1014-1987 Rev C1 compliant. This module is essential for industrial automation, data acquisition, and control systems requiring flexible non-volatile memory expansion.

I. Basic Product Information

Brand: XYCOM (belongs to Acromag Xembedded)

Model: XVME-103, original part number 10103-001 / DS-74103-001

Form: 3U single-height VMEbus standard slave memory expansion board, not including CPU or I/O card

Positioning: To expand independent RAM, EPROM, Flash, EEPROM program / cache storage areas for the entire XVME series VME master control (601/674/675/655)

Life Cycle: Factory-wide complete discontinuation, inventory consists of fully loaded test refurbished boards + a small amount of brand-new original surplus

Bus Role: Pure VME Slave device, A24/A16 address, D16/D08 data width, compatible with IEEE 1014 VME standard

Core Memory Hardware Architecture

Slot Layout

8-channel 32-pin JEDEC standard chip sockets, physically divided into two independent storage Banks, each group with 4 slots; the same Bank must install chips of the same model and speed

Support for storage media and maximum capacity

CMOS RAM: Maximum 4MB (with onboard battery for power failure protection)

EPROM: Maximum 8MB (firmware, control program固化)

Flash ROM： Maximum 4MB

EEPROM： Maximum 4MB (can be online erased formulas， parameters)

Read-write Characteristics

Native support for RMW (read - modify - write) bus cycle， compatible with industrial real-time multi-task memory operations； onboard voltage monitoring， when voltage is lower than 4.75V， memory is locked and reading/writing is prohibited to prevent data damage

 Power Failure Protection and Monitoring Circuit

Built-in lithium battery backup

Specifically supplies power for CMOS RAM， maintains memory data and RTC real-time clock for long-term preservation when the entire VME backplane is powered off

Multiple fault alarm logic (jumper selectable)

Low battery voltage： Red LED "BATT LOW" on the front panel lights up

Backup voltage insufficient： Configurable to trigger SYSFAIL global fault signal or SYSRESET system reset

Status Indicator Lights

Dual-path Bank activity LED on the front panel + battery fault LED， intuitive judgment of storage read/write and power supply status

Electrical and Mechanical Specifications

Power Supply Source： Fully derived from VME backplane P1 connector + 5V DC； control signals transmitted by P2 connector

Power Consumption： Typical working current 0.38A @ +5V， standby backup current extremely low

Form Factor： 3U single-height VME 233.35mm × 100mm standard size

Net Weight： Approximately 0.28kg， PCB with three-proof moisture-proof coating

Environmental Conditions

Standard operating temperature： 0℃ ~ +50℃

Storage temperature： -25℃ ~ +70℃

Humidity 5%–95% no condensation， withstands factory dust， mild vibration， industrial EMI interference； CE industrial safety certification