+void
+psw_set_ac(void);
+
+void
+psw_clr_ac(void);
+
+void
+psw_write_ac(int ac);
+
+int
+psw_read_ac(void);
+
+void
+psw_set_ov(void);
+
+void
+psw_clr_ov(void);
+
+void
+psw_write_ov(int ov);
+
+int
+psw_read_ov(void);
+
+void
+psw_write_p(int p);
+
+void
+psw_compute_parity_bit(void);
+