The MVME-712M is an IO board for the Motorola MVME single board computer. It adds serial, ethernet (AUI) and SCSI ports.

Following description taken from: http://www.m88k.com/mvme712m.html

The MVME712M is used as the interface between Motorola's MVME1xx RISC and CISC Single Board Computers, such as the MVME147S, MVME162, MVME167, and MVME187 families of VMEmodules, and their peripheral devices. A P2 adapter module and cables are supplied for interconnection between the MVME712M and the MVME1xx-family VMEmodule. The MVME712M has four DB-25 connectors for the serial ports, one 36-pin connector for the printer port, one 50-pin connector for the SCSI port, and one DB-15 connector for the Ethernet port. The serial ports may be configured for use as DTE or DCE through jumper arrangements on the MVME712M.

MVME712M Features
Four DB-25 connectors for the serial ports.
The serial ports may be configured for use as DTE or DCE through jumper arrangements on the MVME712M.
One 36-pin connector for the printer port
One AUI connector
One 50pin SCSI port

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Header Description Setting
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J1 Serial Port 1 DCE Configuration No Jumpers

J11 Serial Port 1 DTE Configuration (default) 1-2, 3-4, 5-6, 7-8,
9-10, 11-12, 13-14

J13 Serial Port 3 DCE Configuration No Jumpers

J14 Serial Port 3 DTE Configuration (default) 1-2, 3-4, 5-6, 7-8,
9-10, 11-12, 13-14

J15 Serial Port 4 Clock Configuration Select No Jumpers

J16 Serial Port 2 DCE Configuration No Jumpers

J17 Serial Port 2 DTE Configuration (default) 1-2, 3-4, 5-6, 7-8,
9-10, 11-12, 13-14

J18 Serial Port 4 DCE Configuration No Jumpers

J19 Serial Port 4 DTE Configuration (default) 1-2, 3-4, 5-6, 7-8,
9-10, 11-12, 13-14
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Sourced from ex-BBC spares components, auctioned on Ebay circa 2016.