From ec3fe0e07d81c58ae405820972673bf5c57dafbc Mon Sep 17 00:00:00 2001
From: Paul Mathieu <paul@ponteilla.net>
Date: Mon, 6 Oct 2025 22:40:10 +0200
Subject: [PATCH] Old crc16 is now a .asm

---
 src/crc16.asm | 45 ++++++++++++++++++++++++++++++++++++++++
 src/crc16.s   | 57 ---------------------------------------------------
 2 files changed, 45 insertions(+), 57 deletions(-)
 create mode 100644 src/crc16.asm
 delete mode 100644 src/crc16.s

diff --git a/src/crc16.asm b/src/crc16.asm
new file mode 100644
index 0000000..c08b261
--- /dev/null
+++ b/src/crc16.asm
@@ -0,0 +1,45 @@
+CPU 8086
+
+_start:
+    push bp
+    mov bp, sp
+    mov si, [bp+8]
+    push word [si]
+    mov si, [bp+10]
+    push word [si]
+    call crc16
+    mov di, [bp+6]
+    mov [di], ax
+    mov sp, bp
+    pop bp
+    retf 6
+
+crc16:
+	push	bp
+	mov	bp, sp
+	mov	bx, [bp+4]
+    add [bp+6], bx
+	mov	ax, -1
+.L2:
+	cmp	bx, [bp+6]
+	jne	.L5
+	pop	bp
+	ret
+.L5:
+	mov	dl, [bx]
+	mov	cl, 0x8
+	shl	dx, cl
+	xor ax, dx
+	mov dl, cl
+.L4:
+	mov	cx, ax
+	shl	cx, 1
+	test ax, ax
+	xchg	cx, ax
+	jge	.L3
+	xor	ax, 4129
+.L3:
+	dec	dl
+	jne	.L4
+	inc	bx
+	jmp	.L2
diff --git a/src/crc16.s b/src/crc16.s
deleted file mode 100644
index 5ac8d68..0000000
--- a/src/crc16.s
+++ /dev/null
@@ -1,57 +0,0 @@
-	.arch i8086,jumps
-	.code16
-	.att_syntax prefix
-#NO_APP
-#APP
-    .section .text.init
-    .global _start
-_start:
-
-    .section .text.main
-	.global main      
-main:             
-  push %bp        
-  mov %sp, %bp    
-  mov 8(%bp), %si 
-  push (%si)      
-  call crc16      
-  add $0x2, %sp   
-  mov 6(%bp), %di 
-  mov %ax, (%di)  
-  pop %bp         
-  lret $4         
-
-#NO_APP
-	.text
-	.global	crc16
-	.type	crc16, @function
-crc16:
-	pushw	%bp
-	movw	%sp,	%bp
-	xorw	%bx,	%bx
-	movw	$-1,	%ax
-.L2:
-	cmpw	4(%bp),	%bx
-	jne	.L5
-	popw	%bp
-	ret
-.L5:
-	movb	%cs:(%bx),	%dl
-	movb	$8,	%cl
-	shlw	%cl,	%dx
-	xorw	%dx,	%ax
-	movb	%cl,	%dl
-.L4:
-	movw	%ax,	%cx
-	shlw	$1,	%cx
-	testw	%ax,	%ax
-	xchgw	%ax,	%cx
-	jge	.L3
-	xorw	$4129,	%ax
-.L3:
-	decb	%dl
-	jne	.L4
-	incw	%bx
-	jmp	.L2
-	.size	crc16, .-crc16
-	.ident	"GCC: (GNU) 6.3.0"