Functional Description

The PCCchip2 provides an auto-strobe feature similar to that of the MVME147 PCC.

In auto-strobe mode, after a write to the Printer Data Register, the PCCchip2 automatically asserts the STROBE* pin for a selected time specified by the Printer Fast Strobe control bit.

In manual mode, the Printer Strobe control bit directly controls the state of the STROBE* pin.

Ethernet Interface

The 82596CA implements the Ethernet transceiver interface. The 82596CA accesses local RAM using DMA operations to perform its normal functions.

The Ethernet transceiver interface is located on the MVME187, and the industry standard connector is located on the MVME712X transition module.

Every MVME187 is assigned an Ethernet Station Address. The address is $08003E2xxxxx where xxxxx is the unique 5-nibble number assigned to the board (i.e., every MVME187 has a different value for xxxxx).

Each module has the Ethernet Station Address displayed on a label attached to the VMEbus P2 connector. In addition, the six bytes including the Ethernet address are stored in the configuration area of the BBRAM. That is, 08003E2xxxxx is stored in the BBRAM.

At an address of $FFFC1F2C, the upper four bytes (08003E2x) can be read.

At an address of $FFFC1F30, the lower two bytes (xxxx) can be read.

The MVME187 debugger has the capability to retrieve or set the Ethernet address.

If the data in the BBRAM is lost, the user should use the number on the VMEbus P2 connector label to restore it.

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Motorola MVME187 manual Ethernet Interface