From 6ac16fd1ae275fb4042ab4aa85df3ccc86f3e615 Mon Sep 17 00:00:00 2001
From: Kartik Agaram <vc@akkartik.com>
Date: Sun, 20 Dec 2020 23:52:21 -0800
Subject: 7369 - read hard disk using BIOS

There were two problems:
  a) We have only 1 sector per track (spt=1), so 'second sector' is meaningless.
  b) Drives 0-127 are reserved for floppies.
---
 apps/boot.hex | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'apps/boot.hex')

diff --git a/apps/boot.hex b/apps/boot.hex
index fc80b442..a95c1de7 100644
--- a/apps/boot.hex
+++ b/apps/boot.hex
@@ -34,10 +34,10 @@
 # 00:
 # load_disk:
   b4 02  # ah <- 2  # read sectors from disk
-  b2 00  # dl <- 0  # drive 0
+  b2 80  # dl <- 80  # hdd 0
   b5 00  # ch <- 0  # cylinder 0
   b6 00  # dh <- 0  # track 0
-  b1 02  # cl <- 2  # sector 1 (second sector, 1-based)
+  b1 01  # cl <- 1  # sector 0 (first sector, 1-based)
   b0 01  # al <- 1  # number of sectors to read
   # address to write sectors to = es:bx = 0x7e00, contiguous with boot segment
   bb 00 00  # bx <- 0
-- 
cgit 1.4.1-2-gfad0