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 .

.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;