ReactOS  0.4.15-dev-1171-gab82533
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)