This file describes how to connect a TI Explorer to be debugged by a
Lambda as debug master.

Plugged into a Lambda Multibus slot via a carrier card, is a Burr Brown
parallel interface.  The interface should be configurred in accordance
with the directions in the file BURR-BROWN.

Plugged into the second slot from the left in the Explorer card cage is
the explorer debug card.  The component side of the board faces to the
right.  It might be helpful to use a Nubus extender card when plugging
in this board since its wire-wrap pns might not clear the board in slot
one.  In this case. protect the board prom being shorted by the metal
inner door of the expolrer cabinet.  There are no DIP switches or
jumpers to be configured on this card.

A TI microprocessor in its card cage can most conveniently be placed on
the top of the explorer.  This card cage contains a power supply, a
backplane and to PC boards.  The board in slot one (furthest from the
power supply) has a 64 pin DIP in the middle and two 25 pin D connectors
on the outside edge.  The edge connector on this outside edhe is unused.
We shall refer to the D connector located centermost on the outside edge
of this board as the TI MICRO SERIAL PORT.  The other D connector is
unused.

On this board is a red toggle switch which is spring loaded so that it
is always pointing toward the unused edge connector.  There is also a
dip switch.  The five switches on this dip are labeled from 1 to 5 and
there states are labelled "off" and "on."  Of these switches, only
switch one is in the "on" position.  The rest are "off."

The second board in the TI microprocessor card cage goes in slot three.
The outside edge of this board has two edge connectors on it which we
shall refer to as the SLOT THREE BOARD CENTER CONNECTOR and the SLOT
THREE BOARD OUTER CONNECTOR.  Etched onto the board, near one end of
each of these connectors are the numbers 38 and 39, labelling the ends
of these connectors.  We shall refer to these later.

The component sides of these boards face away from the power supply.

In the back of the explorer, in the leftmost (closest to the power
supply) slot of the bottom row of backplane connectors, is a paddle
card.  At the top of the paddle card are a pushbutton switch and a
toggle switch.  The toggle switch should be in the up position.  This
paddle card also has on it two 40 pin connectors.  The bottom connector
is labeled P3 and the upper connector is labelled P4.

A 50 conductor ribbon cable runs from the bottom (P3) connector on the
Burr Brown card to the DIN connector of the explorer debug card.  The
cable is run such that the bottom edge of the ribbon cable at the Burr
Brown end runs to the bottom end of the DIN connector on the explorer
debug card.  Note that the contacts at top end of the DIN connector are
left open and unused.

A three conductor serial data cable which swaps pins two and three is
run from the TI MICRO SERIAL PORT to goes to the LAMBDA's SDU serial
"local" (female) connector.

A ribbon cable runs from the SLOT THREE BOARD OUTER CONNECTOR to the
upper (P4) connector of the paddle card.  The top edge of the ribbon
cable at the paddle card end connects to the end of the SLOT THREE BOARD
OUTER CONNECTOR which is distinguished by the etches 38 and 39 near it.

A ribbon cable runs from the SLOT THREE BOARD CENTER CONNECTOR to the
lower (P3) connector on the paddle card in the same orientation as for
the P4 to OUTER cable.