add Commen Units

common/CPU/x86/microcode/bound.us

@@ -0,0 +1,36 @@
+// Copyright Jamie Iles, 2017
+//
+// This file is part of s80x86.
+//
+// s80x86 is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// s80x86 is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with s80x86.  If not, see <http://www.gnu.org/licenses/>.
+
+// BOUND
+.at 0x62;
+    mar_write, mar_wr_sel EA, segment DS, jmp_rm_reg_mem bound_reg;
+.auto_address;
+bound_reg:
+    b_sel IMMEDIATE, immediate 0x18, alu_op SELB, tmp_wr_en, jmp do_int;
+bound_mem:
+    alu_op GETFLAGS, tmp_wr_en, segment DS, mem_read;
+    a_sel MDR, b_sel RB, alu_op BOUNDL, update_flags CF;
+    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD, mar_write,
+        mar_wr_sel Q, segment DS, jmp_if_taken bound_fail;
+    segment DS, mem_read;
+    a_sel MDR, b_sel RB, alu_op BOUNDH, update_flags CF;
+    jmp_if_taken bound_fail;
+    b_sel TEMP, alu_op SELB, alu_op SETFLAGSB, update_flags CF, next_instruction;
+
+bound_fail:
+    b_sel TEMP, alu_op SELB, alu_op SETFLAGSB, update_flags CF;
+    b_sel IMMEDIATE, immediate 0x14, alu_op SELB, tmp_wr_en, jmp do_int;