From 1e84b46a5db15645365f1a6b0aefdb7575946576 Mon Sep 17 00:00:00 2001
From: OBattler <oubattler@gmail.com>
Date: Tue, 1 Oct 2024 08:53:57 +0200
Subject: [PATCH] 86F: Correct the obtaining of the preceding bits in direct
 writes, fixes bit stream compliance.

---
 src/floppy/fdd_86f.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/floppy/fdd_86f.c b/src/floppy/fdd_86f.c
index 3fe1428a1..cf9e83694 100644
--- a/src/floppy/fdd_86f.c
+++ b/src/floppy/fdd_86f.c
@@ -1854,6 +1854,7 @@ d86f_write_direct_common(int drive, int side, uint16_t byte, uint8_t type, uint3
     if (type == 0) {
         /* Byte write. */
         encoded_byte = d86f_encode_byte(drive, 0, dbyte, dpbyte);
+        dev->preceding_bit[side] = encoded_byte & 1;
         if (!d86f_reverse_bytes(drive)) {
             mask_data = encoded_byte >> 8;
             encoded_byte &= 0xFF;
@@ -1863,6 +1864,7 @@ d86f_write_direct_common(int drive, int side, uint16_t byte, uint8_t type, uint3
     } else {
         /* Word write. */
         encoded_byte = byte;
+        dev->preceding_bit[side] = (encoded_byte >> 8) & 1;
         if (d86f_reverse_bytes(drive)) {
             mask_data = encoded_byte >> 8;
             encoded_byte &= 0xFF;
@@ -1871,8 +1873,6 @@ d86f_write_direct_common(int drive, int side, uint16_t byte, uint8_t type, uint3
         }
     }
 
-    dev->preceding_bit[side] = encoded_byte & 1;
-
     if (d86f_has_surface_desc(drive)) {
         /* Inverted track data, clear bits are now set. */
         mask_data    = ~dev->track_encoded_data[side][pos];