TSEL Register Decoding:

Register Bit
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7  6  3  2  1  0  Block Selected
0  0  X  X  X  X  186
0  1  X  X  X  X  186
1  X  0  0  0  1  8259
1  X  0  0  1  0  8254
1  X  0  0  1  1  16450
1  X  0  1  0  0  RAM0
1  X  0  1  0  1  RAM1
1  X  0  1  1  0  PARAMETRIC INPUT
1  X  0  1  1  1  PARAMETRIC OUTPUT
1  X  1  X  1  0  TRISTATE LEAKAGE
1  X  1  X  1  1  GAHAN
1  X  0  0  0  0  NO MODULES SELECTED
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