Selection register (S)The Selection register (S) holds the current memory page number (5 bits) and currently selected channel number (4 bits). The remaining 3 bits are not used and always read zero.
bit designation descript
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0 c0 channel number
1 c1 ...
2 c2 ...
3 c3 ...
4 p0 memory page
5 p1 ...
6 p2 ...
7 p3 ...
8 p4 ...
9 0 not used
10 0 not used
11 0 not used
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