1 a1cd4b7f 2024-10-03 benni [cpu 286]
  2 a1cd4b7f 2024-10-03 benni [bits 16]
  3 50eedbae 2024-10-05 benni 
  4 b8971940 2024-10-05 benni %include "macros.inc"
  5 50eedbae 2024-10-05 benni 
  6 c9ad2767 2024-10-07 benni struc TSS
  7 c9ad2767 2024-10-07 benni .link:	resw 1	; +0x00
  8 c9ad2767 2024-10-07 benni .sp0:	resw 1	; +0x02
  9 c9ad2767 2024-10-07 benni .ss0:	resw 1	; +0x04
 10 c9ad2767 2024-10-07 benni .sp1:	resw 1	; +0x06
 11 c9ad2767 2024-10-07 benni .ss1:	resw 1 	; +0x08
 12 c9ad2767 2024-10-07 benni .sp2:	resw 1 	; +0x0a
 13 c9ad2767 2024-10-07 benni .ss2:	resw 1 	; +0x0c
 14 c9ad2767 2024-10-07 benni .ip:	resw 1	; +0x0e
 15 c9ad2767 2024-10-07 benni .flags:	resw 1	; +0x10
 16 c9ad2767 2024-10-07 benni .ax:	resw 1	; +0x12
 17 c9ad2767 2024-10-07 benni .cx:	resw 1	; +0x14
 18 c9ad2767 2024-10-07 benni .dx:	resw 1	; +0x16
 19 c9ad2767 2024-10-07 benni .bx:	resw 1	; +0x18
 20 c9ad2767 2024-10-07 benni .sp:	resw 1	; +0x1a
 21 c9ad2767 2024-10-07 benni .bp:	resw 1	; +0x1c
 22 c9ad2767 2024-10-07 benni .si:	resw 1	; +0x1e
 23 c9ad2767 2024-10-07 benni .di:	resw 1	; +0x20
 24 c9ad2767 2024-10-07 benni .es:	resw 1	; +0x22
 25 c9ad2767 2024-10-07 benni .cs:	resw 1	; +0x24
 26 c9ad2767 2024-10-07 benni .ss:	resw 1	; +0x26
 27 c9ad2767 2024-10-07 benni .ds:	resw 1	; +0x28
 28 c9ad2767 2024-10-07 benni .ldtr:	resw 1	; +0x2a
 29 c9ad2767 2024-10-07 benni .size:		; +0x2c
 30 c9ad2767 2024-10-07 benni endstruc
 31 c9ad2767 2024-10-07 benni 
 32 a1cd4b7f 2024-10-03 benni section .text
 33 9990f831 2024-10-05 benni extern floppy_init
 34 a1cd4b7f 2024-10-03 benni global _entry
 35 9990f831 2024-10-05 benni global putchar
 36 9990f831 2024-10-05 benni global puts
 37 9990f831 2024-10-05 benni global puthexb
 38 9990f831 2024-10-05 benni global puthexw
 39 9990f831 2024-10-05 benni global panic
 40 a1cd4b7f 2024-10-03 benni _entry:
 41 a1cd4b7f 2024-10-03 benni 	pop dx
 42 a1cd4b7f 2024-10-03 benni 	mov byte [bootdrv], dl
 43 a1cd4b7f 2024-10-03 benni 
 44 79ff103d 2024-10-07 benni 	; copy user task into 0x2000:0
 45 79ff103d 2024-10-07 benni 	mov ax, 0x2000
 46 79ff103d 2024-10-07 benni 	mov es, ax
 47 79ff103d 2024-10-07 benni 	xor di, di
 48 79ff103d 2024-10-07 benni 	lea si, [user]
 49 79ff103d 2024-10-07 benni 	lea cx, [user.end - user]
 50 79ff103d 2024-10-07 benni 	rep movsb
 51 79ff103d 2024-10-07 benni 
 52 a64d9d6e 2024-10-05 benni 	; clear screen
 53 a64d9d6e 2024-10-05 benni 	mov bx, 0xb800
 54 a64d9d6e 2024-10-05 benni 	mov es, bx
 55 a64d9d6e 2024-10-05 benni 	xor di, di
 56 a64d9d6e 2024-10-05 benni 	mov ax, (' ' | (0x07 << 8))
 57 a64d9d6e 2024-10-05 benni 	mov cx, (80 * 25 * 2)
 58 a64d9d6e 2024-10-05 benni 	rep stosw
 59 a64d9d6e 2024-10-05 benni 
 60 a1cd4b7f 2024-10-03 benni 	; get size of conventional memory (below 640K)
 61 a1cd4b7f 2024-10-03 benni 	int 0x12
 62 a1cd4b7f 2024-10-03 benni 	mov word [convmem], ax
 63 a1cd4b7f 2024-10-03 benni 
 64 a1cd4b7f 2024-10-03 benni 	; get size of extended memory (above 1M)
 65 a1cd4b7f 2024-10-03 benni 	mov ah, 0x88
 66 a1cd4b7f 2024-10-03 benni 	int 0x15
 67 a1cd4b7f 2024-10-03 benni 	jc .noxm
 68 a1cd4b7f 2024-10-03 benni 	mov word [highmem], ax
 69 a1cd4b7f 2024-10-03 benni 
 70 a1cd4b7f 2024-10-03 benni .noxm:
 71 ce2fe607 2024-10-05 benni 	; NOTE: BIOS cannot be accessed from here
 72 a64d9d6e 2024-10-05 benni 	cli
 73 ce2fe607 2024-10-05 benni 
 74 ce2fe607 2024-10-05 benni 	; disable keyboard
 75 ce2fe607 2024-10-05 benni 	call .wait
 76 ce2fe607 2024-10-05 benni 	mov al, 0xAD
 77 ce2fe607 2024-10-05 benni 	out 0x64, al
 78 ce2fe607 2024-10-05 benni 
 79 ce2fe607 2024-10-05 benni 	; read from input
 80 ce2fe607 2024-10-05 benni 	call .wait
 81 ce2fe607 2024-10-05 benni 	mov al, 0xD0
 82 ce2fe607 2024-10-05 benni 	out 0x64, al
 83 ce2fe607 2024-10-05 benni 	call .wait2
 84 ce2fe607 2024-10-05 benni 	in al, 0x60
 85 ce2fe607 2024-10-05 benni 	mov bl, al
 86 ce2fe607 2024-10-05 benni 
 87 ce2fe607 2024-10-05 benni 	; write to output
 88 ce2fe607 2024-10-05 benni 	call .wait
 89 ce2fe607 2024-10-05 benni 	mov al,0xD1
 90 ce2fe607 2024-10-05 benni 	out 0x64,al
 91 ce2fe607 2024-10-05 benni 	call .wait
 92 ce2fe607 2024-10-05 benni 	mov al, bl
 93 ce2fe607 2024-10-05 benni 	or al, 2	; enable A20 line
 94 ce2fe607 2024-10-05 benni 	out 0x60, al
 95 ce2fe607 2024-10-05 benni 
 96 ce2fe607 2024-10-05 benni 	; enable keyboard
 97 ce2fe607 2024-10-05 benni 	call .wait
 98 ce2fe607 2024-10-05 benni 	mov al, 0xAE
 99 ce2fe607 2024-10-05 benni 	out 0x64, al
100 ce2fe607 2024-10-05 benni 	call .wait
101 ce2fe607 2024-10-05 benni 	jmp .setup
102 ce2fe607 2024-10-05 benni 
103 ce2fe607 2024-10-05 benni .wait:
104 ce2fe607 2024-10-05 benni 	in al,0x64
105 ce2fe607 2024-10-05 benni 	test al, 2
106 ce2fe607 2024-10-05 benni 	jnz .wait
107 ce2fe607 2024-10-05 benni 	ret
108 ce2fe607 2024-10-05 benni 
109 ce2fe607 2024-10-05 benni 
110 ce2fe607 2024-10-05 benni .wait2:
111 ce2fe607 2024-10-05 benni 	in      al,0x64
112 ce2fe607 2024-10-05 benni 	test    al,1
113 ce2fe607 2024-10-05 benni 	jz      .wait2
114 ce2fe607 2024-10-05 benni 	ret
115 ce2fe607 2024-10-05 benni 
116 ce2fe607 2024-10-05 benni .setup:
117 a64d9d6e 2024-10-05 benni 	lidt [idtr]
118 a64d9d6e 2024-10-05 benni 	lgdt [gdtr]
119 a64d9d6e 2024-10-05 benni 	smsw ax
120 a64d9d6e 2024-10-05 benni 	or ax, 1
121 a64d9d6e 2024-10-05 benni 	lmsw ax
122 0f506373 2024-10-07 benni 	jmp (gdt.text - gdt):.reloadcs
123 a1cd4b7f 2024-10-03 benni 
124 50eedbae 2024-10-05 benni .reloadcs:
125 a64d9d6e 2024-10-05 benni 	lea sp, [stack]
126 0f506373 2024-10-07 benni 	lea ax, [gdt.data - gdt]
127 a64d9d6e 2024-10-05 benni 	mov ds, ax
128 a64d9d6e 2024-10-05 benni 	mov es, ax
129 a64d9d6e 2024-10-05 benni 	mov ss, ax
130 50eedbae 2024-10-05 benni 
131 50eedbae 2024-10-05 benni 	; initialize PIC
132 50eedbae 2024-10-05 benni 	outb_slow 0x20, 0x11	; Start the initialization routine (in cascae mode)
133 50eedbae 2024-10-05 benni 	outb_slow 0xA0, 0x11
134 50eedbae 2024-10-05 benni 	outb_slow 0x21, 0x20	; Master PIC IRQ offset
135 50eedbae 2024-10-05 benni 	outb_slow 0xA1, 0x28	; Slave PIC IRQ offset
136 50eedbae 2024-10-05 benni 	outb_slow 0x21, 4	; Tell the master PIC that there is a slave PIC at IRQ2
137 50eedbae 2024-10-05 benni 	outb_slow 0xA1, 2	; Tell the slave PIC it's cascade identity
138 50eedbae 2024-10-05 benni 	outb_slow 0x21, 1	; Use the 8086-mode (and not the 8088 mode)
139 50eedbae 2024-10-05 benni 	outb_slow 0xA1, 1
140 50eedbae 2024-10-05 benni 	outb_slow 0x21, 0xfe	; Set the IRQ masks
141 50eedbae 2024-10-05 benni 	outb_slow 0xA1, 0xff
142 50eedbae 2024-10-05 benni 
143 50eedbae 2024-10-05 benni 	; initialize IDT
144 50eedbae 2024-10-05 benni 	mov al, 0x20
145 50eedbae 2024-10-05 benni 	mov ah, 0x86
146 50eedbae 2024-10-05 benni 	lea dx, [i_timer]
147 50eedbae 2024-10-05 benni 	call set_irq
148 79ff103d 2024-10-07 benni 	mov al, 0x80
149 79ff103d 2024-10-07 benni 	mov ah, 0xe6
150 79ff103d 2024-10-07 benni 	lea dx, [i_sys]
151 79ff103d 2024-10-07 benni 	call set_irq
152 50eedbae 2024-10-05 benni 
153 3a5c7209 2024-10-05 benni 	lea bp, [convmsg]
154 3a5c7209 2024-10-05 benni 	call puts
155 3a5c7209 2024-10-05 benni 	mov ax, word [convmem]
156 3a5c7209 2024-10-05 benni 	call puthexw
157 3a5c7209 2024-10-05 benni 	lea bp, [kbmsg]
158 3a5c7209 2024-10-05 benni 	call puts
159 3a5c7209 2024-10-05 benni 
160 3a5c7209 2024-10-05 benni 	lea bp, [xmmsg]
161 3a5c7209 2024-10-05 benni 	call puts
162 3a5c7209 2024-10-05 benni 	mov ax, word [highmem]
163 3a5c7209 2024-10-05 benni 	call puthexw
164 3a5c7209 2024-10-05 benni 	lea bp, [kbmsg]
165 3a5c7209 2024-10-05 benni 	call puts
166 3a5c7209 2024-10-05 benni 
167 9990f831 2024-10-05 benni 	call floppy_init
168 9990f831 2024-10-05 benni 
169 c9ad2767 2024-10-07 benni 	; set up TSS
170 c9ad2767 2024-10-07 benni 	mov word [tss + TSS.link], 0
171 c9ad2767 2024-10-07 benni 	mov word [tss + TSS.sp0], stack
172 0f506373 2024-10-07 benni 	mov word [tss + TSS.ss0], (gdt.data - gdt)
173 c9ad2767 2024-10-07 benni 
174 c9ad2767 2024-10-07 benni 	; load TSS into TR
175 c9ad2767 2024-10-07 benni 	lea ax, [gdt.tss - gdt]
176 c9ad2767 2024-10-07 benni 	ltr ax
177 5cd42ecd 2024-10-07 benni 
178 5cd42ecd 2024-10-07 benni 	; load LDT
179 5cd42ecd 2024-10-07 benni 	lea ax, [gdt.ldt - gdt]
180 5cd42ecd 2024-10-07 benni 	lldt ax
181 c9ad2767 2024-10-07 benni 
182 e3a03814 2024-10-07 benni 	; enter userspace, TODO: enter ring 3
183 79ff103d 2024-10-07 benni 	mov ax, 0x0f		; LDT .data
184 e3a03814 2024-10-07 benni 	mov ds, ax
185 74abebce 2024-10-07 benni 	mov es, ax
186 79ff103d 2024-10-07 benni 	push 0x17		; ss (LDT .stack)
187 79ff103d 2024-10-07 benni 	push 0xfffe		; sp
188 0f506373 2024-10-07 benni 	push 0x202		; flags (EI | 0x02)
189 79ff103d 2024-10-07 benni 	push 0x07		; cs (LDT .text)
190 79ff103d 2024-10-07 benni 	push 0			; ip
191 e3a03814 2024-10-07 benni 	iret
192 a1cd4b7f 2024-10-03 benni 
193 50eedbae 2024-10-05 benni i_timer:
194 50eedbae 2024-10-05 benni 	pusha
195 79ff103d 2024-10-07 benni 	push ds
196 79ff103d 2024-10-07 benni 	push es
197 79ff103d 2024-10-07 benni 
198 79ff103d 2024-10-07 benni 	mov ax, (gdt.data - gdt)
199 79ff103d 2024-10-07 benni 	mov ds, ax
200 79ff103d 2024-10-07 benni 	mov es, ax
201 79ff103d 2024-10-07 benni 
202 50eedbae 2024-10-05 benni 	mov al, '.'
203 50eedbae 2024-10-05 benni 	call putchar
204 50eedbae 2024-10-05 benni 	
205 50eedbae 2024-10-05 benni 	outb 0x20, 0x20
206 79ff103d 2024-10-07 benni 	pop es
207 79ff103d 2024-10-07 benni 	pop ds
208 50eedbae 2024-10-05 benni 	popa
209 50eedbae 2024-10-05 benni 	iret
210 50eedbae 2024-10-05 benni 
211 79ff103d 2024-10-07 benni ; ds:si - from
212 79ff103d 2024-10-07 benni ; es:di - to
213 79ff103d 2024-10-07 benni ; cx - count
214 79ff103d 2024-10-07 benni copy_from_user:
215 79ff103d 2024-10-07 benni 	rep movsb
216 79ff103d 2024-10-07 benni 	ret
217 79ff103d 2024-10-07 benni 
218 79ff103d 2024-10-07 benni i_sys:	; syscall interrupt (0x80)
219 79ff103d 2024-10-07 benni 	push ds
220 79ff103d 2024-10-07 benni 	push es
221 79ff103d 2024-10-07 benni 
222 ae4ed8c5 2024-10-07 benni 	; load kernel .data into es
223 79ff103d 2024-10-07 benni 	push ax
224 79ff103d 2024-10-07 benni 	mov ax, (gdt.data - gdt)
225 79ff103d 2024-10-07 benni 	mov es, ax
226 79ff103d 2024-10-07 benni 	pop ax
227 79ff103d 2024-10-07 benni 
228 79ff103d 2024-10-07 benni 	test ax, ax
229 79ff103d 2024-10-07 benni 	jz .print
230 79ff103d 2024-10-07 benni 
231 79ff103d 2024-10-07 benni 	; invalid interrupt
232 79ff103d 2024-10-07 benni 	mov ax, -1
233 79ff103d 2024-10-07 benni 	jmp .ret
234 79ff103d 2024-10-07 benni 
235 79ff103d 2024-10-07 benni 
236 79ff103d 2024-10-07 benni .print:
237 79ff103d 2024-10-07 benni 	push cx
238 79ff103d 2024-10-07 benni 	mov si, bx
239 79ff103d 2024-10-07 benni 	lea di, [ubuf]
240 79ff103d 2024-10-07 benni 	; TODO: check that cx < sizeof(ubuf)
241 79ff103d 2024-10-07 benni 	call copy_from_user
242 79ff103d 2024-10-07 benni 	pop bx
243 79ff103d 2024-10-07 benni 	mov byte [ubuf + bx], 0
244 79ff103d 2024-10-07 benni 
245 ae4ed8c5 2024-10-07 benni 	; load kernel .data into ds & es
246 79ff103d 2024-10-07 benni 	lea ax, [gdt.data - gdt]
247 79ff103d 2024-10-07 benni 	mov ds, ax
248 79ff103d 2024-10-07 benni 	mov es, ax
249 ae4ed8c5 2024-10-07 benni 
250 79ff103d 2024-10-07 benni 	lea bp, [ubuf]
251 e3a03814 2024-10-07 benni 	call puts
252 79ff103d 2024-10-07 benni 	xor ax, ax
253 79ff103d 2024-10-07 benni 	jmp .ret
254 79ff103d 2024-10-07 benni 
255 79ff103d 2024-10-07 benni .ret:
256 79ff103d 2024-10-07 benni 	pop es
257 79ff103d 2024-10-07 benni 	pop ds
258 79ff103d 2024-10-07 benni 	iret
259 e3a03814 2024-10-07 benni 
260 50eedbae 2024-10-05 benni ; al - num
261 50eedbae 2024-10-05 benni ; ah - attr
262 50eedbae 2024-10-05 benni ; dx - offset
263 50eedbae 2024-10-05 benni set_irq:
264 50eedbae 2024-10-05 benni 	xor bh, bh
265 50eedbae 2024-10-05 benni 	mov bl, al
266 50eedbae 2024-10-05 benni 	shl bx, 3
267 50eedbae 2024-10-05 benni 	lea bx, [idt + bx]
268 50eedbae 2024-10-05 benni 	mov word [bx + 0], dx
269 0f506373 2024-10-07 benni 	mov word [bx + 2], (gdt.text - gdt)
270 50eedbae 2024-10-05 benni 	mov byte [bx + 4], 0x00
271 50eedbae 2024-10-05 benni 	mov byte [bx + 5], ah
272 50eedbae 2024-10-05 benni 	mov word [bx + 6], 0
273 50eedbae 2024-10-05 benni 	ret
274 50eedbae 2024-10-05 benni 
275 a1cd4b7f 2024-10-03 benni error:
276 a64d9d6e 2024-10-05 benni 	cli
277 a1cd4b7f 2024-10-03 benni 	lea bp, [errstr]
278 a64d9d6e 2024-10-05 benni 	call puts
279 a64d9d6e 2024-10-05 benni 	hlt
280 a64d9d6e 2024-10-05 benni 	jmp $
281 a1cd4b7f 2024-10-03 benni 
282 3a5c7209 2024-10-05 benni ; ax - value
283 3a5c7209 2024-10-05 benni puthexw:
284 3a5c7209 2024-10-05 benni 	push ax
285 3a5c7209 2024-10-05 benni 	mov al, ah
286 3a5c7209 2024-10-05 benni 	call puthexb
287 3a5c7209 2024-10-05 benni 	pop ax
288 3a5c7209 2024-10-05 benni 	jmp puthexb
289 3a5c7209 2024-10-05 benni 
290 3a5c7209 2024-10-05 benni ; al - value
291 3a5c7209 2024-10-05 benni puthexb:
292 3a5c7209 2024-10-05 benni 	push ax
293 3a5c7209 2024-10-05 benni 	shr al, 4
294 3a5c7209 2024-10-05 benni 	call puthexch
295 3a5c7209 2024-10-05 benni 	pop ax
296 3a5c7209 2024-10-05 benni 	and al, 0xf
297 3a5c7209 2024-10-05 benni 	jmp puthexch
298 3a5c7209 2024-10-05 benni 
299 3a5c7209 2024-10-05 benni ; al - hex digit
300 3a5c7209 2024-10-05 benni puthexch:
301 3a5c7209 2024-10-05 benni 	cmp al, 10
302 3a5c7209 2024-10-05 benni 	jae .hex
303 3a5c7209 2024-10-05 benni 	add al, '0'
304 3a5c7209 2024-10-05 benni 	jmp putchar
305 3a5c7209 2024-10-05 benni 
306 3a5c7209 2024-10-05 benni .hex:
307 3a5c7209 2024-10-05 benni 	add al, 'a' - 10
308 3a5c7209 2024-10-05 benni 	jmp putchar
309 3a5c7209 2024-10-05 benni 
310 a64d9d6e 2024-10-05 benni ; al - char
311 50eedbae 2024-10-05 benni writech:
312 0f506373 2024-10-07 benni 	lea bx, [gdt.vid - gdt]
313 a64d9d6e 2024-10-05 benni 	mov es, bx
314 a64d9d6e 2024-10-05 benni 
315 a64d9d6e 2024-10-05 benni 	xor ch, ch
316 a64d9d6e 2024-10-05 benni 	xor dh, dh
317 a64d9d6e 2024-10-05 benni 	mov cl, byte [posx]
318 a64d9d6e 2024-10-05 benni 	mov dl, byte [posy]
319 a64d9d6e 2024-10-05 benni 
320 a64d9d6e 2024-10-05 benni 	cmp al, 10	; '\n'
321 a64d9d6e 2024-10-05 benni 	je .nl
322 a64d9d6e 2024-10-05 benni 
323 a64d9d6e 2024-10-05 benni 	imul bx, dx, 80
324 a64d9d6e 2024-10-05 benni 	add bx, cx
325 a64d9d6e 2024-10-05 benni 	shl bx, 1
326 a64d9d6e 2024-10-05 benni 	mov byte [es:bx], al
327 a64d9d6e 2024-10-05 benni 	
328 a64d9d6e 2024-10-05 benni 	inc cl
329 a64d9d6e 2024-10-05 benni 	cmp cl, 80
330 a64d9d6e 2024-10-05 benni 	je .nl
331 a64d9d6e 2024-10-05 benni 	mov byte [posx], cl
332 a64d9d6e 2024-10-05 benni 	ret
333 a64d9d6e 2024-10-05 benni 
334 a64d9d6e 2024-10-05 benni .nl:
335 a64d9d6e 2024-10-05 benni 	mov byte [posx], 0
336 a64d9d6e 2024-10-05 benni 	inc dl
337 a64d9d6e 2024-10-05 benni 
338 a64d9d6e 2024-10-05 benni 	cmp dl, 25
339 a64d9d6e 2024-10-05 benni 	je .scroll
340 a64d9d6e 2024-10-05 benni 	mov byte [posy], dl
341 a64d9d6e 2024-10-05 benni 	ret
342 a64d9d6e 2024-10-05 benni 
343 a64d9d6e 2024-10-05 benni .scroll:
344 b6729e0b 2024-10-05 benni 	push ds
345 b6729e0b 2024-10-05 benni 	mov ax, 0x18
346 b6729e0b 2024-10-05 benni 	mov ds, ax
347 b6729e0b 2024-10-05 benni 
348 a64d9d6e 2024-10-05 benni 	cld
349 a64d9d6e 2024-10-05 benni 	xor di, di
350 b6729e0b 2024-10-05 benni 	mov si, 160
351 b6729e0b 2024-10-05 benni 	mov cx, 80 * 24
352 a64d9d6e 2024-10-05 benni 	rep movsw
353 a64d9d6e 2024-10-05 benni 
354 b6729e0b 2024-10-05 benni 	pop ds
355 b6729e0b 2024-10-05 benni 
356 b6729e0b 2024-10-05 benni 	mov di, 80 * 24 * 2
357 b6729e0b 2024-10-05 benni 	mov cx, 80
358 a64d9d6e 2024-10-05 benni 	mov ax, (' ' | (0x07 << 8))
359 a64d9d6e 2024-10-05 benni 	rep stosw
360 a64d9d6e 2024-10-05 benni 	mov byte [posy], 24
361 a64d9d6e 2024-10-05 benni 	ret
362 a64d9d6e 2024-10-05 benni 
363 50eedbae 2024-10-05 benni ; al - ch
364 50eedbae 2024-10-05 benni putchar:
365 50eedbae 2024-10-05 benni 	call writech
366 50eedbae 2024-10-05 benni 	jmp update_cursor
367 50eedbae 2024-10-05 benni 
368 a64d9d6e 2024-10-05 benni ; bp - str
369 a1cd4b7f 2024-10-03 benni puts:
370 a1cd4b7f 2024-10-03 benni 	mov al, byte [ds:bp]
371 a1cd4b7f 2024-10-03 benni 	inc bp
372 a1cd4b7f 2024-10-03 benni 	test al, al
373 50eedbae 2024-10-05 benni 	jz update_cursor
374 a1cd4b7f 2024-10-03 benni 
375 50eedbae 2024-10-05 benni 	call writech
376 a1cd4b7f 2024-10-03 benni 	jmp puts
377 a1cd4b7f 2024-10-03 benni 
378 50eedbae 2024-10-05 benni update_cursor:
379 a64d9d6e 2024-10-05 benni 	mov dx, 0x3D4
380 a64d9d6e 2024-10-05 benni 	mov al, 0x0f
381 a64d9d6e 2024-10-05 benni 	out dx, al
382 a64d9d6e 2024-10-05 benni 
383 a64d9d6e 2024-10-05 benni 	mov bx, word [posy]
384 a64d9d6e 2024-10-05 benni 	imul bx, 80
385 a64d9d6e 2024-10-05 benni 	add bx, word [posx]
386 a64d9d6e 2024-10-05 benni 
387 a64d9d6e 2024-10-05 benni 	inc dx		; 0x3D5
388 a64d9d6e 2024-10-05 benni 	mov al, bl
389 a64d9d6e 2024-10-05 benni 	out dx, al
390 a64d9d6e 2024-10-05 benni 
391 a64d9d6e 2024-10-05 benni 	dec dx		; 0x3D4
392 a64d9d6e 2024-10-05 benni 	mov al, 0x0E
393 a64d9d6e 2024-10-05 benni 	out dx, al
394 a64d9d6e 2024-10-05 benni 
395 a64d9d6e 2024-10-05 benni 	inc dx		; 0x3D5
396 a64d9d6e 2024-10-05 benni 	mov al, bh
397 a64d9d6e 2024-10-05 benni 	out dx, al
398 a1cd4b7f 2024-10-03 benni 	ret
399 4dc7f0b4 2024-10-05 benni 
400 4dc7f0b4 2024-10-05 benni ; bp - str
401 4dc7f0b4 2024-10-05 benni panic:
402 4dc7f0b4 2024-10-05 benni 	call puts
403 a1cd4b7f 2024-10-03 benni 
404 4dc7f0b4 2024-10-05 benni .halt:
405 4dc7f0b4 2024-10-05 benni 	cli
406 4dc7f0b4 2024-10-05 benni 	hlt
407 4dc7f0b4 2024-10-05 benni 	jmp .halt
408 4dc7f0b4 2024-10-05 benni 
409 a1cd4b7f 2024-10-03 benni section .rodata
410 79ff103d 2024-10-07 benni user:
411 79ff103d 2024-10-07 benni 	incbin "user.bin"
412 79ff103d 2024-10-07 benni .end:
413 a1cd4b7f 2024-10-03 benni hello:
414 a64d9d6e 2024-10-05 benni 	db "Hello World", 10, 0
415 a1cd4b7f 2024-10-03 benni errstr:
416 a64d9d6e 2024-10-05 benni 	db "Error", 10, 0
417 3a5c7209 2024-10-05 benni convmsg:
418 3a5c7209 2024-10-05 benni 	db "Conventional memory: 0x", 0
419 3a5c7209 2024-10-05 benni xmmsg:
420 3a5c7209 2024-10-05 benni 	db "Extended memory: 0x", 0
421 3a5c7209 2024-10-05 benni kbmsg:
422 3a5c7209 2024-10-05 benni 	db " KB", 10, 0
423 a1cd4b7f 2024-10-03 benni 
424 a64d9d6e 2024-10-05 benni align 2
425 a1cd4b7f 2024-10-03 benni idtr:
426 a1cd4b7f 2024-10-03 benni 	dw idt.end - idt - 1
427 a64d9d6e 2024-10-05 benni 	dd idt + 0x10000
428 a1cd4b7f 2024-10-03 benni 
429 a64d9d6e 2024-10-05 benni align 2
430 a1cd4b7f 2024-10-03 benni gdtr:
431 a1cd4b7f 2024-10-03 benni 	dw gdt.end - gdt - 1
432 a64d9d6e 2024-10-05 benni 	dd gdt + 0x10000
433 a1cd4b7f 2024-10-03 benni 
434 a64d9d6e 2024-10-05 benni 
435 a64d9d6e 2024-10-05 benni section .data
436 a1cd4b7f 2024-10-03 benni gdt:
437 a1cd4b7f 2024-10-03 benni 	dq 0
438 a64d9d6e 2024-10-05 benni 
439 c9ad2767 2024-10-07 benni .text:	; 0x08 - kernel code
440 a64d9d6e 2024-10-05 benni 	dw 0xffff
441 a64d9d6e 2024-10-05 benni 	dw 0x0000
442 a64d9d6e 2024-10-05 benni 	db 0x01
443 a64d9d6e 2024-10-05 benni 	db 0x9A
444 a64d9d6e 2024-10-05 benni 	dw 0x0000
445 a64d9d6e 2024-10-05 benni 
446 c9ad2767 2024-10-07 benni .data:	; 0x10 - kernel data
447 a64d9d6e 2024-10-05 benni 	dw 0xffff
448 a64d9d6e 2024-10-05 benni 	dw 0x0000
449 a64d9d6e 2024-10-05 benni 	db 0x01
450 a64d9d6e 2024-10-05 benni 	db 0x92
451 a64d9d6e 2024-10-05 benni 	dw 0x0000
452 a64d9d6e 2024-10-05 benni 
453 c9ad2767 2024-10-07 benni .vid:	; 0x18 - video memory
454 a64d9d6e 2024-10-05 benni 	dw 4000
455 a64d9d6e 2024-10-05 benni 	dw 0x8000
456 a64d9d6e 2024-10-05 benni 	db 0x0b
457 a64d9d6e 2024-10-05 benni 	db 0x92
458 a64d9d6e 2024-10-05 benni 	dw 0x0000
459 c9ad2767 2024-10-07 benni 	
460 c9ad2767 2024-10-07 benni .tss:	; 0x20 - TSS
461 c9ad2767 2024-10-07 benni 	dw TSS.size
462 c9ad2767 2024-10-07 benni 	dw tss
463 c9ad2767 2024-10-07 benni 	db 0x01
464 c9ad2767 2024-10-07 benni 	db 0x81
465 c9ad2767 2024-10-07 benni 	dw 0x0000
466 c9ad2767 2024-10-07 benni 
467 5cd42ecd 2024-10-07 benni .ldt:	; 0x28 - LDT
468 5cd42ecd 2024-10-07 benni 	dw (ldt.end - ldt)
469 5cd42ecd 2024-10-07 benni 	dw ldt
470 5cd42ecd 2024-10-07 benni 	db 0x01
471 5cd42ecd 2024-10-07 benni 	db 0x82
472 5cd42ecd 2024-10-07 benni 	dw 0x0000
473 a1cd4b7f 2024-10-03 benni .end:
474 a1cd4b7f 2024-10-03 benni 
475 5cd42ecd 2024-10-07 benni ldt:
476 5cd42ecd 2024-10-07 benni .text:	; 0x07 - user code
477 5cd42ecd 2024-10-07 benni 	dw 0xffff
478 5cd42ecd 2024-10-07 benni 	dw 0x0000
479 5cd42ecd 2024-10-07 benni 	db 0x02
480 5cd42ecd 2024-10-07 benni 	db 0xfa
481 5cd42ecd 2024-10-07 benni 	dw 0x0000
482 5cd42ecd 2024-10-07 benni 
483 5cd42ecd 2024-10-07 benni .data:	; 0x0f - user data
484 5cd42ecd 2024-10-07 benni 	dw 0xffff
485 5cd42ecd 2024-10-07 benni 	dw 0x0000
486 5cd42ecd 2024-10-07 benni 	db 0x02
487 5cd42ecd 2024-10-07 benni 	db 0xf2
488 5cd42ecd 2024-10-07 benni 	dw 0x0000
489 5cd42ecd 2024-10-07 benni 
490 5cd42ecd 2024-10-07 benni .stack:	; 0x17 - user stack
491 5cd42ecd 2024-10-07 benni 	dw 0xffff
492 5cd42ecd 2024-10-07 benni 	dw 0x0000
493 5cd42ecd 2024-10-07 benni 	db 0x03
494 5cd42ecd 2024-10-07 benni 	db 0xf2
495 5cd42ecd 2024-10-07 benni 	dw 0x0000
496 5cd42ecd 2024-10-07 benni .end:
497 5cd42ecd 2024-10-07 benni 
498 a1cd4b7f 2024-10-03 benni section .bss
499 79ff103d 2024-10-07 benni ubuf:
500 79ff103d 2024-10-07 benni 	resb 256
501 a64d9d6e 2024-10-05 benni posx:
502 a64d9d6e 2024-10-05 benni 	resw 1
503 a64d9d6e 2024-10-05 benni posy:
504 a64d9d6e 2024-10-05 benni 	resw 1
505 a1cd4b7f 2024-10-03 benni bootdrv:
506 a1cd4b7f 2024-10-03 benni 	resb 1
507 a1cd4b7f 2024-10-03 benni convmem:
508 a1cd4b7f 2024-10-03 benni 	resw 1	; in kilobytes
509 a1cd4b7f 2024-10-03 benni highmem:
510 a1cd4b7f 2024-10-03 benni 	resw 1	; in kilobytes
511 a1cd4b7f 2024-10-03 benni idt:
512 a1cd4b7f 2024-10-03 benni 	resq 256
513 a1cd4b7f 2024-10-03 benni .end:
514 a64d9d6e 2024-10-05 benni 	resb 512
515 a64d9d6e 2024-10-05 benni stack:
516 c9ad2767 2024-10-07 benni tss:
517 c9ad2767 2024-10-07 benni 	resb TSS.size