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\begin{document}
\author{John Butler}
\title{The EYEBALL board}
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\section{The MicronEye camera and board}

A full description can be found in the MicronEye operator's manual, Appendix G.

The Department should have three copies of this (one for each camera).

The PCB is actually an Apple-2 board but for interfacing purposes it need only
be noted that the circuit described in Appendix G is actually driven from RS232.

This circuit is common to all variants of the circuit (PC/Apple-2/Commodore etc.)
and customisation for the Apple-2 is achieved by putting a 6850 ACIA on board to
drive the RS232 line.   All the APM interface does is to provide some address
decoding and bus buffering to drive this.

The edge connector on the Apple-2 board uses the following pins:
\begin{tabbing}
mmmmmm\=mmmmmmmmmmmmmmmmmmmmmm\=\kill
 2 \> A0 \\
18 \> r/w' \\
25 \> +5v \\
26 \> 0? \\
40 \> Clk \\
41 \> Dev Sel' \\
42 \> D0 \\
43 \> D1 \\
44 \> D2 \\
45 \> D3 \\
46 \> D4 \\
47 \> D5 \\
48 \> D6 \\
49 \> D7 \\

The r/w' line drives a 245 bus buffer. \\
Dev Sel' drives CS2' on the ACIA. \\
A0 goes into the ACIA RS line \\

\section{The Zapped interface}
\section{The BEPI interface}
\end{document}
