reorganisation des fichiers
This commit is contained in:
Frater
parent
ac89c58ddb
commit
27c70ba1e6
6 changed files with 565 additions and 544 deletions
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@ -88,45 +88,6 @@ endstruc
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; 0x03C00-0x08000 : stack segment
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; 0x
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; -----------------------------------------------------------------------------------
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; PC components I/O ports
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; -----------------------------------------------------------------------------------
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; controleur clavier/souris i8042 (AT-PS/2)
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%define i8042_PS2_DATA 0x60
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%define i8042_PS2_CTRL 0x64
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; PIC 8259 ports (Programmable Interrupt Controller)
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; PIC 1 : Master
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%define i8259_MASTER_CMD 0x20
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%define i8259_MASTER_DATA 0x21
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; PIC 2 : Slave
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%define i8259_SLAVE_CMD 0xA0
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%define i8259_SLAVE_DATA 0xA1
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; i8259 Commands
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%define ICW1_ICW4 0x01 ; Indicates that ICW4 will be present
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%define ICW1_SINGLE 0x02 ; Single (cascade) mode
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%define ICW1_INTERVAL4 0x04 ; Call address interval 4 (8)
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%define ICW1_LEVEL 0x08 ; Level triggered (edge) mode
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%define ICW1_INIT 0x10 ; Initialization - required!
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%define ICW4_8086 0x01 ; 8086/88 (MCS-80/85) mode
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%define ICW4_AUTO 0x02 ; Auto (normal) EOI
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%define ICW4_BUF_SLAVE 0x08 ; Buffered mode/slave
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%define ICW4_BUF_MASTER 0x0C ; Buffered mode/master
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%define ICW4_SFNM 0x10 ; Special fully nested (not)
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%define PIC_EOI 0x20
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; Remap : IRQ0..7 -> 0x08..0x0F, IRQ8..15 -> 0x70..0x77
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%define i8259_MASTER_INT 0x08
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%define i8259_SLAVE_INT 0x70
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%define IRQ_ENABLED 0x00
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%define IRQ_DISABLED 0x01
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; -----------------------------------------------------------------------------------
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; bda_setup
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; Initialise la BDA à zéro
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@ -1,102 +0,0 @@
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; ============================================================================
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; Font 8x8 (printable ASCII 0x20..0x7E) -> 95 glyphs * 8 = 760 bytes
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; - bit7 = gauche, bit0 = droite
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; - 1 byte = 1 scanline (haut -> bas)
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; ============================================================================
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font8x8:
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db 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 ; 0x20 ' '
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db 0x18,0x18,0x18,0x18,0x18,0x00,0x18,0x00 ; 0x21 '!'
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db 0x66,0x66,0x24,0x00,0x00,0x00,0x00,0x00 ; 0x22 '"'
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db 0x24,0x24,0x7E,0x24,0x7E,0x24,0x24,0x00 ; 0x23 '#'
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db 0x18,0x3E,0x60,0x3C,0x06,0x7C,0x18,0x00 ; 0x24 '$'
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db 0x62,0x66,0x0C,0x18,0x30,0x66,0x46,0x00 ; 0x25 '%'
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db 0x38,0x6C,0x38,0x76,0xDC,0xCC,0x76,0x00 ; 0x26 '&'
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db 0x18,0x18,0x30,0x00,0x00,0x00,0x00,0x00 ; 0x27 '''
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db 0x0C,0x18,0x30,0x30,0x30,0x18,0x0C,0x00 ; 0x28 '('
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db 0x30,0x18,0x0C,0x0C,0x0C,0x18,0x30,0x00 ; 0x29 ')'
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db 0x00,0x66,0x3C,0xFF,0x3C,0x66,0x00,0x00 ; 0x2A '*'
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db 0x00,0x18,0x18,0x7E,0x18,0x18,0x00,0x00 ; 0x2B '+'
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db 0x00,0x00,0x00,0x00,0x00,0x18,0x18,0x30 ; 0x2C ','
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db 0x00,0x00,0x00,0x7E,0x00,0x00,0x00,0x00 ; 0x2D '-'
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db 0x00,0x00,0x00,0x00,0x00,0x18,0x18,0x00 ; 0x2E '.'
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db 0x06,0x0C,0x18,0x30,0x60,0xC0,0x80,0x00 ; 0x2F '/'
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db 0x3C,0x66,0x6E,0x76,0x66,0x66,0x3C,0x00 ; 0x30 '0'
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db 0x18,0x38,0x18,0x18,0x18,0x18,0x3C,0x00 ; 0x31 '1'
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db 0x3C,0x66,0x06,0x0C,0x18,0x30,0x7E,0x00 ; 0x32 '2'
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db 0x3C,0x66,0x06,0x1C,0x06,0x66,0x3C,0x00 ; 0x33 '3'
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db 0x0C,0x1C,0x3C,0x6C,0x7E,0x0C,0x0C,0x00 ; 0x34 '4'
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db 0x7E,0x60,0x7C,0x06,0x06,0x66,0x3C,0x00 ; 0x35 '5'
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db 0x1C,0x30,0x60,0x7C,0x66,0x66,0x3C,0x00 ; 0x36 '6'
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db 0x7E,0x66,0x06,0x0C,0x18,0x18,0x18,0x00 ; 0x37 '7'
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db 0x3C,0x66,0x66,0x3C,0x66,0x66,0x3C,0x00 ; 0x38 '8'
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db 0x3C,0x66,0x66,0x3E,0x06,0x0C,0x38,0x00 ; 0x39 '9'
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db 0x00,0x18,0x18,0x00,0x00,0x18,0x18,0x00 ; 0x3A ':'
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db 0x00,0x18,0x18,0x00,0x00,0x18,0x18,0x30 ; 0x3B ';'
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db 0x0E,0x1C,0x38,0x70,0x38,0x1C,0x0E,0x00 ; 0x3C '<'
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db 0x00,0x00,0x7E,0x00,0x7E,0x00,0x00,0x00 ; 0x3D '='
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db 0x70,0x38,0x1C,0x0E,0x1C,0x38,0x70,0x00 ; 0x3E '>'
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db 0x3C,0x66,0x06,0x0C,0x18,0x00,0x18,0x00 ; 0x3F '?'
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db 0x3C,0x66,0x6E,0x6A,0x6E,0x60,0x3C,0x00 ; 0x40 '@'
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db 0x18,0x3C,0x66,0x66,0x7E,0x66,0x66,0x00 ; 0x41 'A'
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db 0x7C,0x66,0x66,0x7C,0x66,0x66,0x7C,0x00 ; 0x42 'B'
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db 0x3C,0x66,0x60,0x60,0x60,0x66,0x3C,0x00 ; 0x43 'C'
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db 0x78,0x6C,0x66,0x66,0x66,0x6C,0x78,0x00 ; 0x44 'D'
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db 0x7E,0x60,0x60,0x7C,0x60,0x60,0x7E,0x00 ; 0x45 'E'
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db 0x7E,0x60,0x60,0x7C,0x60,0x60,0x60,0x00 ; 0x46 'F'
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db 0x3C,0x66,0x60,0x6E,0x66,0x66,0x3C,0x00 ; 0x47 'G'
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db 0x66,0x66,0x66,0x7E,0x66,0x66,0x66,0x00 ; 0x48 'H'
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db 0x3C,0x18,0x18,0x18,0x18,0x18,0x3C,0x00 ; 0x49 'I'
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db 0x1E,0x0C,0x0C,0x0C,0x0C,0x6C,0x38,0x00 ; 0x4A 'J'
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db 0x66,0x6C,0x78,0x70,0x78,0x6C,0x66,0x00 ; 0x4B 'K'
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db 0x60,0x60,0x60,0x60,0x60,0x60,0x7E,0x00 ; 0x4C 'L'
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db 0x63,0x77,0x7F,0x6B,0x63,0x63,0x63,0x00 ; 0x4D 'M'
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db 0x66,0x76,0x7E,0x7E,0x6E,0x66,0x66,0x00 ; 0x4E 'N'
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db 0x3C,0x66,0x66,0x66,0x66,0x66,0x3C,0x00 ; 0x4F 'O'
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db 0x7C,0x66,0x66,0x7C,0x60,0x60,0x60,0x00 ; 0x50 'P'
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db 0x3C,0x66,0x66,0x66,0x6E,0x3C,0x0E,0x00 ; 0x51 'Q'
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db 0x7C,0x66,0x66,0x7C,0x78,0x6C,0x66,0x00 ; 0x52 'R'
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db 0x3C,0x66,0x60,0x3C,0x06,0x66,0x3C,0x00 ; 0x53 'S'
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db 0x7E,0x18,0x18,0x18,0x18,0x18,0x18,0x00 ; 0x54 'T'
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db 0x66,0x66,0x66,0x66,0x66,0x66,0x3C,0x00 ; 0x55 'U'
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db 0x66,0x66,0x66,0x66,0x66,0x3C,0x18,0x00 ; 0x56 'V'
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db 0x63,0x63,0x63,0x6B,0x7F,0x77,0x63,0x00 ; 0x57 'W'
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db 0x66,0x66,0x3C,0x18,0x3C,0x66,0x66,0x00 ; 0x58 'X'
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db 0x66,0x66,0x66,0x3C,0x18,0x18,0x18,0x00 ; 0x59 'Y'
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db 0x7E,0x06,0x0C,0x18,0x30,0x60,0x7E,0x00 ; 0x5A 'Z'
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db 0x3C,0x30,0x30,0x30,0x30,0x30,0x3C,0x00 ; 0X5B '['
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db 0xC0,0x60,0x30,0x18,0x0C,0x06,0x02,0x00 ; 0x5C '\'
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db 0x3C,0x0C,0x0C,0x0C,0x0C,0x0C,0x3C,0x00 ; 0x5D ']'
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db 0x10,0x38,0x6C,0xC6,0x00,0x00,0x00,0x00 ; 0x5E '^'
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db 0x00,0x00,0x00,0x00,0x00,0x00,0xFF,0x00 ; 0x5F '_'
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db 0x30,0x18,0x0C,0x00,0x00,0x00,0x00,0x00 ; 0x60 '`'
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db 0x00,0x00,0x3C,0x06,0x3E,0x66,0x3E,0x00 ; 0x61 'a'
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db 0x60,0x60,0x7C,0x66,0x66,0x66,0x7C,0x00 ; 0x62 'b'
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db 0x00,0x00,0x3C,0x66,0x60,0x66,0x3C,0x00 ; 0x63 'c'
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db 0x06,0x06,0x3E,0x66,0x66,0x66,0x3E,0x00 ; 0x64 'd'
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db 0x00,0x00,0x3C,0x66,0x7E,0x60,0x3C,0x00 ; 0x65 'e'
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db 0x1C,0x30,0x30,0x7C,0x30,0x30,0x30,0x00 ; 0x66 'f'
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db 0x00,0x00,0x3E,0x66,0x66,0x3E,0x06,0x3C ; 0x67 'g'
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db 0x60,0x60,0x7C,0x66,0x66,0x66,0x66,0x00 ; 0x68 'h'
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db 0x18,0x00,0x38,0x18,0x18,0x18,0x3C,0x00 ; 0x69 'i'
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db 0x0C,0x00,0x0C,0x0C,0x0C,0x6C,0x6C,0x38 ; 0x6A 'j'
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db 0x60,0x60,0x66,0x6C,0x78,0x6C,0x66,0x00 ; 0x6B 'k'
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db 0x38,0x18,0x18,0x18,0x18,0x18,0x3C,0x00 ; 0x6C 'l'
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db 0x00,0x00,0x6C,0x7E,0x7E,0x6B,0x63,0x00 ; 0x6D 'm'
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db 0x00,0x00,0x7C,0x66,0x66,0x66,0x66,0x00 ; 0x6E 'n'
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db 0x00,0x00,0x3C,0x66,0x66,0x66,0x3C,0x00 ; 0x6F 'o'
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db 0x00,0x00,0x7C,0x66,0x66,0x7C,0x60,0x60 ; 0x70 'p'
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db 0x00,0x00,0x3E,0x66,0x66,0x3E,0x06,0x06 ; 0x71 'q'
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db 0x00,0x00,0x6C,0x76,0x60,0x60,0x60,0x00 ; 0x72 'r'
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db 0x00,0x00,0x3E,0x60,0x3C,0x06,0x7C,0x00 ; 0x73 's'
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db 0x30,0x30,0x7C,0x30,0x30,0x30,0x1C,0x00 ; 0x74 't'
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db 0x00,0x00,0x66,0x66,0x66,0x66,0x3E,0x00 ; 0x75 'u'
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db 0x00,0x00,0x66,0x66,0x66,0x3C,0x18,0x00 ; 0x76 'v'
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db 0x00,0x00,0x63,0x63,0x6B,0x7F,0x36,0x00 ; 0x77 'w'
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db 0x00,0x00,0x66,0x3C,0x18,0x3C,0x66,0x00 ; 0x78 'x'
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db 0x00,0x00,0x66,0x66,0x66,0x3E,0x06,0x3C ; 0x79 'y'
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db 0x00,0x00,0x7E,0x0C,0x18,0x30,0x7E,0x00 ; 0x7A 'z'
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db 0x0E,0x18,0x18,0x70,0x18,0x18,0x0E,0x00 ; 0x7B '{'
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db 0x18,0x18,0x18,0x00,0x18,0x18,0x18,0x00 ; 0x7C '|'
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db 0x70,0x18,0x18,0x0E,0x18,0x18,0x70,0x00 ; 0x7D '}'
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db 0x76,0xDC,0x00,0x00,0x00,0x00,0x00,0x00 ; 0x7E '~'
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264
src/common/generic.asm
Normal file
264
src/common/generic.asm
Normal file
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@ -0,0 +1,264 @@
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; =============================================================================
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; Project : Custom BIOS / ROM
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; File : generic.asm
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; Author : frater
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;
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; License : GNU General Public License v3.0 or later (GPL-3.0+)
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;
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; This program is free software: you can redistribute it and/or modify
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; it under the terms of the GNU General Public License as published by
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; the Free Software Foundation, either version 3 of the License, or
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; (at your option) any later version.
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;
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; This program is distributed in the hope that it will be useful,
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; but WITHOUT ANY WARRANTY; without even the implied warranty of
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; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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; GNU General Public License for more details.
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;
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; You should have received a copy of the GNU General Public License
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; along with this program. If not, see <https://www.gnu.org/licenses/>.
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;
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; =============================================================================
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; -----------------------------------------------------------------------------------
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; PC components I/O ports
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; -----------------------------------------------------------------------------------
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; controleur clavier/souris i8042 (AT-PS/2)
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%define i8042_PS2_DATA 0x60
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%define i8042_PS2_CTRL 0x64
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; PIC 8259 ports (Programmable Interrupt Controller)
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; PIC 1 : Master
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%define i8259_MASTER_CMD 0x20
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%define i8259_MASTER_DATA 0x21
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; PIC 2 : Slave
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%define i8259_SLAVE_CMD 0xA0
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%define i8259_SLAVE_DATA 0xA1
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; i8259 Commands
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%define ICW1_ICW4 0x01 ; Indicates that ICW4 will be present
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%define ICW1_SINGLE 0x02 ; Single (cascade) mode
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%define ICW1_INTERVAL4 0x04 ; Call address interval 4 (8)
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%define ICW1_LEVEL 0x08 ; Level triggered (edge) mode
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%define ICW1_INIT 0x10 ; Initialization - required!
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%define ICW4_8086 0x01 ; 8086/88 (MCS-80/85) mode
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%define ICW4_AUTO 0x02 ; Auto (normal) EOI
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%define ICW4_BUF_SLAVE 0x08 ; Buffered mode/slave
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%define ICW4_BUF_MASTER 0x0C ; Buffered mode/master
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%define ICW4_SFNM 0x10 ; Special fully nested (not)
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%define PIC_EOI 0x20
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; Remap : IRQ0..7 -> 0x08..0x0F, IRQ8..15 -> 0x70..0x77
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%define i8259_MASTER_INT 0x08
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%define i8259_SLAVE_INT 0x70
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%define IRQ_ENABLED 0x00
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%define IRQ_DISABLED 0x01
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; ---------------------------------------------------------------------------
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; Détection les ROM supplementaires
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; Teste la RAM de 0xC000 jusqu’à 0xE000, par pas de 2KB.
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;
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; Si une ROM est détectée, le code de la ROM sera appelé.
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; ---------------------------------------------------------------------------
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setup_load_rom:
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mov bx, 0xC000
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.scanloop:
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mov ds, bx
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cmp word[0x0000],0xAA55 ; ROM signature
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jne .norom
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; appel le code (en 0x0003) de la ROM
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push cs
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push word .norom ; address de retour
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push ds
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push 0x0003
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retf ; call far ds:0x0003
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.norom:
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add bx, 0x80 ; add 2kb
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cmp bx, 0xE000
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jbe .scanloop
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.end:
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ret
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; ---------------------------------------------------------------------------
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; Test si le vecteur INT 10h à été modifié (par la ROM)
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;
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; Si le vecteur n'a pas été modifiée, on considère que la ROM video n'a pas
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; été chargée.
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; ---------------------------------------------------------------------------
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setup_check_vga:
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; vérification de l'offset 0x0000:0x0040 qui DOIT etre différent de @default_isr
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xor ax,ax
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mov es,ax
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; Lire INT10: offset+segment depuis 0000:0040
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mov bx, [es:0x0040] ; BX = offset INT10
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mov cx, [es:0x0042] ; CX = segment INT10
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mov ax, cs
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; Comparer avec default_isr (offset) et CS (segment)
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mov dx, default_isr ; DX = offset default_isr (dans notre CS)
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cmp bx, dx
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jne .init_ok ; vecteur different, bios initialisé
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cmp cx, ax
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jne .init_ok
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mov ax,cs ; vecteur identique, sans doute pas d'initialisation
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mov ds,ax
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.init_ok:
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ret
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; ---------------------------------------------------------------------------
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; IVT install (8088, mode réel) - remplit les 256 vecteurs avec un handler IRET
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; ---------------------------------------------------------------------------
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ivt_setup:
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; installation de la table d'interrupts
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xor ax, ax
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mov es, ax ; ES = 0000h -> base IVT
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xor di, di ; DI = 0000h -> offset IVT
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mov ax, default_isr ; offset du handler
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mov dx, cs ; segment du handler (ROM)
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mov cx, 256 ; 256 vecteurs
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||||
.fill:
|
||||
stosw ; write offset (AX) -> [ES:DI], DI += 2
|
||||
xchg ax, dx ; AX = segment, DX = offset
|
||||
stosw ; write segment (AX) -> [ES:DI], DI += 2
|
||||
xchg ax, dx ; AX = offset, DX = segment
|
||||
loop .fill
|
||||
; fin de la table d'interrupt
|
||||
ret
|
||||
|
||||
; ---------------------------------------------------------------------------
|
||||
; IVT install (8088, mode réel) - installe un handler a une interrupt calculée
|
||||
;
|
||||
; ax = int id
|
||||
; dx = segment handler
|
||||
; bx = offset handler
|
||||
; ---------------------------------------------------------------------------
|
||||
ivt_setvector:
|
||||
push es
|
||||
push di
|
||||
|
||||
shl ax,2 ; ax=id *4
|
||||
mov di,ax
|
||||
|
||||
xor ax,ax
|
||||
mov es, ax ; ES = 0000h -> base IVT
|
||||
|
||||
mov ax, bx ; offset du handler
|
||||
cli
|
||||
stosw ; write offset (AX) -> [ES:DI], DI += 2
|
||||
xchg ax, dx ; AX = segment, DX = offset
|
||||
stosw ; write segment (AX) -> [ES:DI], DI += 2
|
||||
sti
|
||||
|
||||
pop di
|
||||
pop es
|
||||
ret
|
||||
|
||||
io_wait:
|
||||
xor al,al
|
||||
out 0x80,al
|
||||
ret
|
||||
|
||||
; ---------------------------------------------------------------------------
|
||||
; Initialise les PIC 8259 (PC/AT):
|
||||
; - Master offset 0x08
|
||||
; - Slave offset 0x70
|
||||
; - Cascade: IRQ2
|
||||
; https://wiki.nox-rhea.org/back2root/ibm-pc-ms-dos/hardware/8259
|
||||
; ---------------------------------------------------------------------------
|
||||
pic_init:
|
||||
cli
|
||||
push ax
|
||||
|
||||
; force un End Of Interrupt sur les 2 PIC
|
||||
mov al, 0x20
|
||||
out i8259_SLAVE_CMD, al ; EOI PIC esclave
|
||||
out i8259_MASTER_CMD, al ; EOI PIC maître
|
||||
|
||||
; starts the initialization sequence (in cascade mode)
|
||||
mov al, ICW1_INIT | ICW1_ICW4
|
||||
out i8259_MASTER_CMD, al
|
||||
out i8259_SLAVE_CMD, al
|
||||
|
||||
mov al, i8259_MASTER_INT
|
||||
out i8259_MASTER_DATA, al ; ICW2: Master PIC vector offset
|
||||
mov al, i8259_SLAVE_INT
|
||||
out i8259_SLAVE_DATA, al ; ICW2: Slave PIC vector offset
|
||||
|
||||
; Master: cascade (IRQ2 => 1 << IRQ2 = 0x04)
|
||||
mov al, 0x04 ; master: slave on IRQ2: 0100b
|
||||
out i8259_MASTER_DATA, al ; ICW3: tell Master PIC that there is a slave PIC at IRQ2
|
||||
|
||||
; Slave: numéro de ligne sur master (2)
|
||||
mov al, 0x02 ; slave: cascade identity 2
|
||||
out i8259_SLAVE_DATA, al ; ICW3: tell Slave PIC its cascade identity (0000 0010)
|
||||
|
||||
; ICW4: 8086 mode
|
||||
mov al, ICW4_8086
|
||||
out i8259_MASTER_DATA, al
|
||||
out i8259_SLAVE_DATA, al
|
||||
|
||||
pop ax
|
||||
ret
|
||||
|
||||
; ------------------------------------------------------------------
|
||||
; set_irq_mask
|
||||
; AH = 0 (Enable/Unmask) ou 1 (Disable/Mask)
|
||||
; AL = Numéro de l'IRQ (0 à 15)
|
||||
; ------------------------------------------------------------------
|
||||
pic_set_irq_mask:
|
||||
pusha
|
||||
|
||||
mov cl, al ; CL = numéro d'IRQ
|
||||
; Par défaut, PIC Maître (Data port)
|
||||
mov dx, i8259_MASTER_DATA
|
||||
|
||||
cmp cl, 8
|
||||
jl .is_master
|
||||
|
||||
; Si IRQ >= 8, on passe sur le PIC Esclave
|
||||
sub cl, 8 ; Ajuste l'index du bit (8-15 -> 0-7)
|
||||
; Port Data du PIC Esclave
|
||||
mov dx, i8259_SLAVE_DATA
|
||||
|
||||
.is_master:
|
||||
; Préparation du masque de bit
|
||||
mov bl, 1
|
||||
shl bl, cl ; BL contient maintenant le bit correspondant (ex: IRQ 3 -> 00001000)
|
||||
|
||||
in al, dx ; Lire l'IMR actuel depuis le port (0x21 ou 0xA1)
|
||||
|
||||
test ah, ah ; AH est-il à 1 (Disable) ?
|
||||
jnz .do_disable
|
||||
|
||||
.do_enable:
|
||||
not bl ; Inverser le masque (ex: 11110111)
|
||||
and al, bl ; Mettre le bit à 0 (Unmask)
|
||||
jmp .write_back
|
||||
|
||||
.do_disable:
|
||||
or al, bl ; Mettre le bit à 1 (Mask)
|
||||
|
||||
.write_back:
|
||||
out dx, al ; Écrire le nouveau masque dans l'IMR
|
||||
|
||||
popa
|
||||
ret
|
||||
|
||||
; ---------------------------------------------------------------------------
|
||||
; Handler par défaut: fait juste IRET
|
||||
; IMPORTANT: doit être FAR (appelé par le CPU via IVT), et terminer par IRET
|
||||
; ---------------------------------------------------------------------------
|
||||
default_isr:
|
||||
iret
|
||||
|
||||
Loading…
Reference in a new issue