難しい・・・><;
関数電卓コラム
10/02/24 関数電卓のしくみ(CORDICアルゴルズム)
https://teamcoil.sp.u-tokai.ac.jp/calculators/column/100224/index.html
Programming:Sin/Cos calculation - CPCWiki https://www.cpcwiki.eu/index.php/Programming:Sin/Cos_calculation
Z80 Number Cruncher http://www.andreadrian.de/oldcpu/Z80_number_cruncher.html