Subversion Repositories s80186

// 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;