From 3f18fce879256f287fb0b456ca34b31bb01f5476 Mon Sep 17 00:00:00 2001
From: Paul Gardner-Stephen <paul@servalproject.org>
Date: Sat, 20 Apr 2019 01:01:05 +0930
Subject: [PATCH] unroll loop in keyboard scanner

---
 c64/kernal/scan_keyboard.s | 50 ++++++++------------------------------
 1 file changed, 10 insertions(+), 40 deletions(-)

diff --git a/c64/kernal/scan_keyboard.s b/c64/kernal/scan_keyboard.s
index 4b81e6ee..e2113e02 100644
--- a/c64/kernal/scan_keyboard.s
+++ b/c64/kernal/scan_keyboard.s
@@ -314,47 +314,17 @@ skip0:
     ;; //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     ;; // Scan Keyboard Matrix
 
-    lda #%11111110
-    sta $dc00
-    ldy $dc01
-    sty ScanResult+7
-    sec
-
+	ldx #7
+	lda #%11111110
+*	sta $dc00
+	pha
+	lda $dc01
+	sta ScanResult,x
+	pla
+	sec
         rol
-        sta $dc00
-        ldy $dc01
-        sty ScanResult+6
-
-        rol
-        sta $dc00
-        ldy $dc01
-        sty ScanResult+5
-
-        rol
-        sta $dc00
-        ldy $dc01
-        sty ScanResult+4
-
-        rol
-        sta $dc00
-        ldy $dc01
-        sty ScanResult+3
-
-        rol
-        sta $dc00
-        ldy $dc01
-        sty ScanResult+2
-
-        rol
-        sta $dc00
-        ldy $dc01
-        sty ScanResult+1
-
-        rol
-        sta $dc00
-        ldy $dc01
-        sty ScanResult+0
-
+	dex
+	bpl -
 
 
     ;; //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~