mirror of
https://github.com/Gehstock/Mist_FPGA.git
synced 2026-01-18 09:02:08 +00:00
59 lines
2.1 KiB
Plaintext
59 lines
2.1 KiB
Plaintext
// 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 0xaa;
|
|
width W8, ra_sel AL, jmp stosb;
|
|
|
|
.auto_address;
|
|
stosb:
|
|
width W8, a_sel RA, alu_op SELA, mdr_write;
|
|
ra_sel DI, rb_cl, jmp_if_not_rep stosb_no_rep;
|
|
stosb_rep_loop:
|
|
ra_sel CX, jmp_rb_zero stosb_done;
|
|
ra_sel DI, a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op SUB,
|
|
rd_sel_source MICROCODE_RD_SEL, rd_sel CX;
|
|
stosb_no_rep:
|
|
ra_sel DI, a_sel RA, alu_op SELA, mar_wr_sel Q, mar_write;
|
|
a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op NEXT,
|
|
rd_sel_source MICROCODE_RD_SEL, rd_sel DI;
|
|
width W8, ra_sel AL;
|
|
width W8, alu_op SELA, mdr_write, segment ES, segment_force;
|
|
width W8, segment ES, segment_force, mem_write, jmp_if_not_rep stosb_done;
|
|
rb_cl, ext_int_yield, jmp stosb_rep_loop;
|
|
stosb_done:
|
|
next_instruction;
|
|
|
|
.at 0xab;
|
|
ra_sel AX, jmp stosw;
|
|
|
|
.auto_address;
|
|
stosw:
|
|
a_sel RA, alu_op SELA, mdr_write,
|
|
ra_sel DI, rb_cl, jmp_if_not_rep stosw_no_rep;
|
|
stosw_rep_loop:
|
|
ra_sel CX, jmp_rb_zero stosw_done;
|
|
ra_sel DI, a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op SUB,
|
|
rd_sel_source MICROCODE_RD_SEL, rd_sel CX;
|
|
stosw_no_rep:
|
|
ra_sel DI, a_sel RA, alu_op SELA, mar_wr_sel Q, mar_write;
|
|
a_sel RA, b_sel IMMEDIATE, immediate 0x2, alu_op NEXT,
|
|
rd_sel_source MICROCODE_RD_SEL, rd_sel DI, segment ES, segment_force;
|
|
segment ES, segment_force, mem_write, jmp_if_not_rep stosw_done;
|
|
rb_cl, ext_int_yield, jmp stosw_rep_loop;
|
|
stosw_done:
|
|
next_instruction;
|