SC128, v1.0, User Guide

There really isn’t much to say about using the modular backplane, SC128. Basically, you just plug in your Z50Bus compatible cards, connect the power, and turn it on.

The only complication is the Z80 mode 2 interrupt daisy chain signals, IEI and IEO. Currently, it is unlikely you will be using this feature.

The interrupt daisy chain consists of a signal that connects the output of one card (IEO) to the input of the next (IEI). The position of a card in the chain (ie. its position on the backplane) determines its interrupt priority. If you are using this feature you must not leave a gap between cards that support interrupts, as this will break the chain.

If you are using mode 2 interrupts and you have either a backplane section or a Z50Bus card fitted to the horizontal bus socket (SK7) then you need to fit a jumper shunt to JP1. This jumper has one position for a backplane section and another for a Z50Bus card.

One thing worth noting is that the ON/OFF switch only turns the system on and off if it is powered from the 5-volt input connectors on the backplane. If power is introduced from a Z50Bus card, such as a serial port, the switch will only isolates that power from the power connectors on the backplane. not from the cards connected to the backplane.

The backplane is a modular design allowing it to be extended using the LiNC 5-slot backplane section.

Alternative, the horizontal socket can be used to connect a Z50Bus card. This can be very useful when debugging hardware.

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