EOMA68 CPU card interface connection guide

EOMA68 CPU card interface EOMA68 v1.0 connector wiring guide with power, signal assignments, and bench checks.

EOMA68 v1.0 connector

68 contacts Current package

EOMA project · Two rows of 34 positions

Required

With the CPU card removed, confirm the connector orientation and check the supply using a keyed breakout on a compatible EOMA68 chassis.

5 V rail
- +5 V (24)
- +5 V (29)
- +5 V (58)
- +5 V (63)
- Voltmeter positive
Return
- GND (31)
- GND (33)
- GND (65)
- GND (67)
- Voltmeter return

Check the chassis startup procedure before energizing the connector.
Confirm a stable 5 V rail and shut down the chassis before inserting the CPU card.

EOMA-68 Specification v1.0, Table of EOMA-68 Pinouts

Use a high-impedance logic analyzer referenced to ground to observe the I²C transaction during a normal cold start.

Set the analyzer threshold for the measured logic rail.
Look for a transaction to 7-bit address 0x51 and an acknowledgment from the chassis.

EOMA-68 Specification v1.0, I²C

Highlighted contacts are used in the required step or selected circuit. Select a contact to inspect it.

Contact numbering from the v1.0 specification. Follow the chassis drawing to identify contact 1.

Per interface · Bus

Check the chassis and CPU card implementation for interface support and multiplexing.

EOMA-68 Specification v1.0, Table of EOMA-68 Pinouts

The map follows the v1.0 table. Check the revision and implemented interfaces on both sides of the connector.

EOMA-68 Specification v1.0· Project specification, connector table, I²C and power sequencing.