Advance on FCB disk i/o

2019-10-12 18:33:26 +00:00 · 2019-10-12 18:33:26 +00:00 · a65f54b121
commit a65f54b121
parent e07e13fd35
4 changed files with 84 additions and 39 deletions
--- a/kernel/drive.asm
+++ b/kernel/drive.asm
@ -67,3 +67,17 @@ drive_read:
  jnz .try
  stc
  jmp .giveup
+
+; Seek to fcb_off given in a ptr
+; IN	BX	ptr to FCB
+drive_seek:
+  push ax
+  push cx
+  mov cl, [bx+fcb_ss]
+  add cl, 7
+  mov ax, 1
+  sal ax, cl
+  int3
+  pop cx
+  pop ax
+  ret