From 31b09f4ab9f5cedbd6893f8b9dfe3698c98d2dd7 Mon Sep 17 00:00:00 2001
From: Wayne Warthen <wwarthen@gmail.com>
Date: Mon, 24 May 2021 11:26:10 -0700
Subject: [PATCH] Update fd.asm

- Improve FDC hardware detection.
---
 Source/HBIOS/fd.asm | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Source/HBIOS/fd.asm b/Source/HBIOS/fd.asm
index 45ed35a9..f4680b98 100644
--- a/Source/HBIOS/fd.asm
+++ b/Source/HBIOS/fd.asm
@@ -743,6 +743,8 @@ FD_INIT0:
 ; DOES NOT ATTEMPT TO DETERMINE THE ACTUAL VARIANT.
 ;
 FD_DETECT:
+	IN	A,(FDC_MSR)	; IGNORE FIRST READ
+	CALL	DLY32		; WAIT A BIT FOR FDC
 	IN	A,(FDC_MSR)	; READ MSR
 	CP	$80
 	JR	Z,FD_DETECT1	; $80 IS OK
@@ -751,6 +753,7 @@ FD_DETECT:
 	RET			; NOPE, ABORT WITH ZF=NZ
 ;
 FD_DETECT1:
+	CALL	DLY32		; WAIT A BIT FOR FDC
 	IN	A,(FDC_MSR)	; READ MSR AGAIN
 	CP	$80
 	RET			; $80 OK, ELSE NOT PRESENT