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<div name="quoted-content">Thanks for the reply, Dave.</div>
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<div name="quoted-content">I have taken a look at the WITCH paper and instruction set. The organisation is quite interesting. At the faculty I've constructed a simple one-address machine, but it was based on binary arithmetic. Dekatrons look exotic, when compared to FFs. For substraction we used two's complement. WITCH must have used ten's complement :)</div>
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<div name="quoted-content">I couldn't find the details on how the control unit was built. Microprogramming was invented in 1947. so there is a chance they used it instead of hard-wired circuits. Are there any more papers on WITCH organization? Architecture is well explained in the instructions.</div>
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<div name="quoted-content">Regards,</div>
<div name="quoted-content">Uroš</div>
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