Serial Mouse (IBM Clone) signals: If it is a microsoft "standard" type, then it sends data in 3 bytes: 1 L R y7 y6 x7 x6 0 x5 x4 x3 x2 x1 x0 0 y5 y4 y3 y2 y1 y0 1200 baud, 7 data bits, no parity (rs-232) If the thing is set to "3 button" mode, the data is sent as a series of 5 bytes: 1 0 0 0 0 L M R x7 x6 x5 x4 x3 x2 x1 x0 y7 y6 y5 y4 y3 y2 y1 y0 (first motion) x7 x6 x5 x4 x3 x2 x1 x0 y7 y6 y5 y4 y3 y2 y1 y0 (second motion, accumulated during the sending of the first 3 bytes) L, M, R are the button bits. 1200 bps, 8 data bits, no parity.
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