Reset floppy disks upon read failure

io.asm

@@ -1,6 +1,8 @@
 ; SPDX-License-Identifier: MIT
 ; Copyright (c) 2021 Juhani 'nortti' Krekelä.
 
+debug equ 1
+
 iosegment equ 60h
 dossegment equ iosegment + 1*1024/16 ; DOS starts 1KiB after IO system
 
@@ -64,8 +66,10 @@ init:
 	shl ax, cl
 	; Memory size is passed in dx
 	mov dx, ax
+if debug
 	call hexprint16
 	call newline
+endif
 
 	; Disk table is passed in si
 	mov si, offset iogroup:disks_table
@@ -94,9 +98,11 @@ init:
 	test al, al
 	jnz open_error
 
+if debug
 	mov al, '+'
 	mov ah, 0eh
 	int 10h
+endif
 
 	; Set random record field 0
 	mov word ptr iogroup:command_fcb+33, 0
@@ -114,12 +120,14 @@ init:
 	cmp al, 1
 	jne read_error
 
+if debug
 	mov ax, cx
 	call hexprint16
 
 	mov al, '.'
 	mov ah, 0eh
 	int 10h
+endif
 
 	; Set up segments for command.com
 	mov ds, bx
@@ -205,6 +213,7 @@ putch endp
 ; OUT:
 ;  TODO: Document
 diskread proc far
+if debug
 	push ax
 	mov ax, 0e00h + 'r'
 	int 10h
@@ -226,6 +235,7 @@ diskread proc far
 	call hexprint16
 	call newline
 	pop ax
+endif
 
 	; TODO: Everything except sregs can be trashed
 	push es
@@ -266,13 +276,25 @@ diskread proc far
 
 			dec di
 			jz sector_read_fail
+
+			reset_disk:
+if debug
+				mov al, '"'
+				mov ah, 0eh
+				int 10h
+endif
+				xor ax, ax
+				int 13h
+
 			pop cx
 			pop ax
 			jmp try_sector_read
 
 		sector_read_fail:
 			mov al, ah
+if debug
 			call hexprint8;debg
+endif
 			mov al, '?'
 			mov ah, 0eh
 			int 10h
@@ -532,7 +554,9 @@ error:
 	mov ah, 0eh
 	mov al, '!'
 	int 10h
+if debug
 	call far_caller
+endif
 
 hang:
 	hlt
@@ -583,6 +607,8 @@ days_since_epoch: dw 0
 data ends
 
 code segment
+if debug
+
 hexprint16 proc
 	xchg al, ah
 	call hexprint8
@@ -672,6 +698,7 @@ logaddr proc
 	ret
 logaddr endp
 
+endif
 code ends
 
 end