From: John Tsiombikas <nuclear@member.fsf.org>
Date: Sat, 12 Oct 2019 11:08:31 +0000 (+0300)
Subject: keyboard interrupt (untested)
X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=ld45_start_nothing;a=commitdiff_plain;h=0216fd8105a2b94aab6eb1c013c97882cacaf0c1

keyboard interrupt (untested)
---

diff --git a/src/intr.inc b/src/intr.inc
index 55a1c9d..ac57934 100644
--- a/src/intr.inc
+++ b/src/intr.inc
@@ -1,9 +1,14 @@
 ; vi:filetype=nasm ts=8 sts=8 sw=8:
 
-%define IRQ_OFFSET	32
+PIC1_CMD	equ 020h
+PIC2_CMD	equ 0a0h
+OCW2_EOI	equ 020h
+OCW3_ISR	equ 00bh
+IRQ_OFFSET	equ 32
 %define IRQ_TO_INTR(x)	((x) + IRQ_OFFSET)
 %define INTR_TO_IRQ(x)	((x) - IRQ_OFFSET)
 
+
 %macro set_irq_vector 2
 	push dword IRQ_TO_INTR(%1)
 	push dword %2
@@ -45,3 +50,7 @@
 %endmacro
 
 	extern idt
+
+%ifndef INTR_ASM_
+	extern set_intr
+%endif
diff --git a/src/kbregs.inc b/src/kbregs.inc
new file mode 100644
index 0000000..8b58ced
--- /dev/null
+++ b/src/kbregs.inc
@@ -0,0 +1,26 @@
+; vi:filetype=nasm ts=8 sts=8 sw=8:
+
+KB_IRQ			equ 1
+KB_DATA_PORT		equ 60h
+KB_CMD_PORT		equ 64h
+KB_STATUS_PORT		equ 64h
+
+KB_ACK			equ 00fah
+KB_NACK			equ 00feh
+KB_TEST_PASS		equ 0055h
+KB_TEST_FAIL		equ 00fch
+
+KB_STAT_OUTBUF_FULL	equ 01h
+KB_STAT_INBUF_FULL	equ 02h
+KB_STAT_SYSFLAG		equ 04h
+KB_STAT_CMD		equ 08h
+KB_STAT_ACTIVE		equ 10h
+KB_STAT_AUX		equ 20h
+KB_STAT_TIMEOUT		equ 40h
+KB_STAT_PAR_ERROR	equ 80h
+
+KB_CMD_GET_CMDBYTE	equ 20h
+KB_CMD_SET_CMDBYTE	equ 60h
+
+KB_CCB_KB_INTREN	equ 01h
+KB_CCB_KB_XLAT		equ 40h
diff --git a/src/keyb.asm b/src/keyb.asm
index 5200f2a..0f1d498 100644
--- a/src/keyb.asm
+++ b/src/keyb.asm
@@ -1,5 +1,107 @@
 ; vi:filetype=nasm ts=8 sts=8 sw=8:
+%include "intr.inc"
+%include "kbregs.inc"
 
 	global kb_init
 kb_init:
-	
+	push kbintr
+	push dword IRQ_TO_INTR(KB_IRQ)
+	call set_intr
+	add esp, 8
+
+	; enable keyboard interrupt
+	mov eax, KB_CMD_GET_CMDBYTE
+	call send_cmd
+	call read_data
+	or eax, KB_CCB_KB_INTREN	; set the INTREN flag
+	push eax
+	mov eax, KB_CMD_SET_CMDBYTE
+	call send_cmd
+	pop eax
+	call send_data
+
+	; flush the read buffer
+	call wait_read
+	jz .skipread
+	call read_data
+.skipread:
+	ret
+
+	; keyboard interrupt handler
+kbintr:
+	pusha
+	in al, KB_DATA_PORT
+	cmp al, 0e0h
+	jnz .noext
+	mov byte [key_ext], 1
+	jmp .eoi
+.noext:
+	; keystate[keycode] address in ebx
+	xor ebx, ebx
+	mov bl, al
+	add ebx, keystate
+
+	; determine if it's a press or release
+	test al, 80h
+	jz .press
+	; key release
+	mov byte [ebx], 0
+	jmp .eoi
+.press: ; key press
+	mov byte [ebx], 1
+
+.eoi:
+	cli
+	end_of_irq KB_IRQ
+
+	popa
+	iret
+
+%macro iodelay 0
+	xor al, al
+	times 7 out 80h, al
+%endmacro
+
+wait_write:
+	push eax
+	push ecx
+	mov ecx, 32768
+.loop:	in al, KB_STATUS_PORT
+	test al, KB_STAT_INBUF_FULL
+	jz .break
+	iodelay
+	dec ecx
+	jnz .loop
+.break: pop ecx
+	pop eax
+	ret
+
+wait_read:
+	push eax
+	push ecx
+	mov ecx, 32768
+.loop:	in al, KB_STATUS_PORT
+	test al, KB_STAT_OUTBUF_FULL
+	jnz .break
+	iodelay
+	dec ecx
+	jnz .loop
+.break: pop ecx
+	pop eax
+	ret
+
+	; expects command in al
+send_cmd:
+	call wait_write
+	out KB_CMD_PORT, al
+	ret
+
+read_data:
+send_data:
+
+	section .data
+	align 4
+key_ext: db 0
+
+	global keystate
+keystate: times 256 db 0
diff --git a/src/keyb.inc b/src/keyb.inc
new file mode 100644
index 0000000..0a6b9a7
--- /dev/null
+++ b/src/keyb.inc
@@ -0,0 +1,3 @@
+; vi:filetype=nasm:
+
+	extern keystate