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testing

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Frater 2026-01-19 09:50:33 +01:00
commit 9cb9033a25
6 changed files with 220 additions and 358 deletions
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64
src/services/generic.asm
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@ -203,55 +203,69 @@ ivt_setvector:
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:
push ax
; ICW1: init + ICW4
mov al, 0x11 ; 000010001b
; starts the initialization sequence (in cascade mode)
mov al, ICW1_INIT | ICW1_ICW4
out i8259_MASTER_CMD, al
call io_wait
mov al, ICW1_INIT | ICW1_ICW4
out i8259_SLAVE_CMD, al
call io_wait
; ICW2: vector offsets
mov al, 0x08
out i8259_MASTER_DATA, al
mov al, 0x70
out i8259_SLAVE_DATA, al
; ICW3: wiring
mov al, 0x04 ; master: slave on IRQ2: 0100b
out i8259_MASTER_DATA, al
mov al, 0x02 ; slave: cascade identity 2
out i8259_SLAVE_DATA, al
mov al, i8259_MASTER_INT
out i8259_MASTER_DATA, al ; ICW2: Master PIC vector offset
call io_wait
mov al, i8259_SLAVE_INT
out i8259_SLAVE_DATA, al ; ICW2: Slave PIC vector offset
call io_wait
; 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
call io_wait
; 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)
call io_wait
; ICW4: 8086 mode
mov al, 0x01
mov al, ICW4_8086
out i8259_MASTER_DATA, al
call io_wait
mov al, ICW4_8086
out i8259_SLAVE_DATA, al
call io_wait
; Masques: unmask IRQ2 (master) et IRQ12 (slave)
in al, i8259_MASTER_DATA
and al, 0xFB ; clear bit2
; Unmask both PICs.
xor al,al
out i8259_MASTER_DATA, al
in al, i8259_SLAVE_DATA
and al, 0xEF ; clear bit4
out i8259_SLAVE_DATA, al
pop ax
ret
; ---------------------------------------------------------------------------
; Handler par défaut: fait juste IRET
; IMPORTANT: doit être FAR (appelé par le CPU via IVT), et terminer par IRET
; ---------------------------------------------------------------------------
default_isr:
iret
iret