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[/] [s80186/] [trunk/] [rtl/] [microcode/] [lods.us] - Rev 2
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// 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/>.
.at 0xac;
jmp lodsb;
.auto_address;
lodsb:
ra_sel SI, rb_cl, jmp_if_not_rep lodsb_no_rep;
lodsb_rep_loop:
ra_sel CX, jmp_rb_zero lodsb_done;
ra_sel SI, a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op SUB,
rd_sel_source MICROCODE_RD_SEL, rd_sel CX;
lodsb_no_rep:
ra_sel SI, a_sel RA, alu_op SELA, mar_wr_sel Q, mar_write, segment DS;
a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op NEXT,
rd_sel_source MICROCODE_RD_SEL, rd_sel SI, segment DS;
width W8, segment DS, mem_read, a_sel MDR, alu_op SELA,
rd_sel_source MICROCODE_RD_SEL, rd_sel AL, jmp_if_not_rep lodsb_done;
rb_cl, ext_int_yield, jmp lodsb_rep_loop;
lodsb_done:
next_instruction;
.at 0xad;
jmp lodsw;
.auto_address;
lodsw:
ra_sel SI, rb_cl, jmp_if_not_rep lodsw_no_rep;
lodsw_rep_loop:
ra_sel CX, jmp_rb_zero lodsw_done;
ra_sel SI, a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op SUB,
rd_sel_source MICROCODE_RD_SEL, rd_sel CX;
lodsw_no_rep:
ra_sel SI, a_sel RA, alu_op SELA, mar_wr_sel Q, mar_write, segment DS;
a_sel RA, b_sel IMMEDIATE, immediate 0x2, alu_op NEXT,
rd_sel_source MICROCODE_RD_SEL, rd_sel SI, segment DS;
segment DS, mem_read, a_sel MDR, alu_op SELA,
rd_sel_source MICROCODE_RD_SEL, rd_sel AX, jmp_if_not_rep lodsw_done;
rb_cl, ext_int_yield, jmp lodsw_rep_loop;
lodsw_done:
next_instruction;