ReactOS 0.4.15-dev-7131-ge4d03f4
cpu.h
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1/*
2 * PROJECT: NEC PC-98 series onboard hardware
3 * LICENSE: GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
4 * PURPOSE: CPU I/O ports header file
5 * COPYRIGHT: Copyright 2020 Dmitry Borisov (di.sean@protonmail.com)
6 */
7
8#pragma once
9
10#define CPU_IO_o_RESET 0xF0
11#define CPU_IO_o_A20_UNMASK 0xF2
12
13#define CPU_IO_o_A20_CONTROL 0xF6
14 #define CPU_A20_ENABLE 0x02
15 #define CPU_A20_DISABLE 0x03
16
17#define CPU_IO_o_FPU_BUSY_LATCH 0xF8
18
19/*
20 * ARTIC (A Relative Time Indication Counter) - 24-bit binary up counter
21 */
22#define CPU_IO_o_ARTIC_DELAY 0x5F /* Constant delay (about 600 ns) */
23#define CPU_IO_i_ARTIC_0 0x5C
24#define CPU_IO_i_ARTIC_1 0x5D
25#define CPU_IO_i_ARTIC_2 0x5E
26#define CPU_IO_i_ARTIC_3 0x5F
27
28#define ARTIC_FREQUENCY 307200
29#define ARTIC_FREQUENCY_0_1 ARTIC_FREQUENCY
30#define ARTIC_FREQUENCY_2_3 (ARTIC_FREQUENCY >> 8)