Add WIP for new debugger

driver/debug.asm

@@ -0,0 +1,76 @@
+	jmp init
+	align 4
+	db "rDos"
+	align 8
+	; hook interrupt 3
+	db 3
+	db 0
+	dw int3entry
+	dd 0
+	; end of header
+	db 0
+
+stacksize: equ 0x20
+
+init:
+	mov ax, 0x0e33
+	xor bx, bx
+	int 0x10
+	retf
+
+int3entry:
+	; save DS and AX
+	mov [cs:reg_ds], ds
+	mov [cs:reg_ax], ax
+	; use AX to load DS=CS
+	mov ax, cs
+	mov ds, ax
+	; pop IP, CS and flags from stack
+	pop ax
+	mov [reg_ip], ax
+	pop ax
+	mov [reg_cs], ax
+	pop ax
+	mov [reg_fl], ax
+	; save the other registers
+	mov [reg_cx], cx
+	mov [reg_dx], dx
+	mov [reg_bx], bx
+	mov [reg_sp], sp
+	mov [reg_bp], bp
+	mov [reg_si], si
+	mov [reg_di], di
+	; save other segment registers we can access
+	mov [reg_ss], ss
+	mov [reg_es], es
+	; initialize other segments and setup stack
+	mov es, ax
+	mov ss, ax
+	mov sp, (stack+stacksize)
+
+hlt:	hlt
+	jmp hlt
+
+reg_ax:	dw 0
+reg_cx:	dw 0
+reg_dx:	dw 0
+reg_bx:	dw 0
+reg_sp:	dw 0
+reg_bp:	dw 0
+reg_si:	dw 0
+reg_di: dw 0
+
+reg_es:	dw 0
+reg_cs:	dw 0
+reg_ss:	dw 0
+reg_ds:	dw 0
+
+reg_ip:	dw 0
+reg_fl:	dw 0
+
+names:	db "AXCXDXBXSPBPSIDI"
+	db "DSESSSCSIPFL"
+
+stack:	times stacksize dw 0
+
+align 16