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 0xc3;
    ra_sel SP, jmp retc3;
.auto_address;
retc3:
    a_sel RA, alu_op SELA, mar_write, mar_wr_sel Q, segment SS,
        segment_force;
    segment SS, segment_force, mem_read;
    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD,
        rd_sel_source MICROCODE_RD_SEL, rd_sel SP;
    a_sel MDR, alu_op SELA, load_ip, next_instruction;

.at 0xc2;
    ra_sel SP, jmp retc2;
.auto_address;
retc2:
    a_sel RA, alu_op SELA, mar_write, mar_wr_sel Q, segment SS,
        segment_force;
    segment SS, segment_force, mem_read;
    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD,
        rd_sel_source MICROCODE_RD_SEL, rd_sel SP;
    a_sel MDR, alu_op SELA, load_ip, read_immed, ra_sel SP;
    a_sel RA, b_sel IMMEDIATE, alu_op ADD, rd_sel_source
        MICROCODE_RD_SEL, rd_sel SP, next_instruction;

.at 0xcb;
    ra_sel SP, jmp retcb;
.auto_address;
retcb:
    a_sel RA, alu_op SELA, mar_write, mar_wr_sel Q, segment SS,
        segment_force;
    segment SS, segment_force, mem_read;
    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD,
        mar_wr_sel Q, mar_write;
    a_sel MDR, alu_op SELA, load_ip, segment_force, segment SS;
    segment SS, segment_force, mem_read;
    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD,
        rd_sel_source MICROCODE_RD_SEL, rd_sel SP;
    a_sel MDR, alu_op SELA, segment_force, segment CS,
        segment_wr_en, next_instruction;

.at 0xca;
    ra_sel SP, jmp retca;
.auto_address;
retca:
    a_sel RA, alu_op SELA, mar_write, mar_wr_sel Q, segment SS,
        segment_force;
    segment SS, segment_force, mem_read;
    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD,
        mar_wr_sel Q, mar_write;
    a_sel MDR, alu_op SELA, load_ip, segment_force, segment SS;
    segment SS, segment_force, mem_read;
    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD,
        mar_wr_sel Q, mar_write;
    read_immed, a_sel MAR, b_sel IMMEDIATE, alu_op ADD,
        rd_sel_source MICROCODE_RD_SEL, rd_sel SP;
    a_sel MDR, alu_op SELA, segment_force, segment CS,
        segment_wr_en, next_instruction;

// iret
.at 0xcf;
    ra_sel SP, jmp retcf;
.auto_address;
retcf:
    a_sel RA, alu_op SELA, mar_write, mar_wr_sel Q, segment SS,
        segment_force;
    segment SS, segment_force, mem_read;
    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD,
        mar_wr_sel Q, mar_write;
    a_sel MDR, alu_op SELA, load_ip, segment_force, segment SS;
    segment SS, segment_force, mem_read;
    a_sel MDR, alu_op SELA, segment_force, segment CS,
        segment_wr_en;
    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD,
        mar_wr_sel Q, mar_write, segment SS, segment_force;
    segment SS, segment_force, mem_read;
    a_sel MDR, alu_op SETFLAGSA, update_flags CF PF AF ZF SF TF IF DF OF;
    a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD,
        rd_sel SP, rd_sel_source MICROCODE_RD_SEL,
        next_instruction;