Added check for disk in drive on chdir().

git-svn-id: svn://svn.cc65.org/cc65/trunk@5859 b7a2c559-68d2-44c3-8de9-860c34a00d81
2012-10-17 20:24:43 +00:00
parent cb668eff63
commit 1a80cd1071
4 changed files with 76 additions and 48 deletions
--- a/libsrc/cbm/diskinit.s
+++ b/libsrc/cbm/diskinit.s
@@ -0,0 +1,53 @@
+;
+; Oliver Schmidt, 2012-10-17
+;
+
+        .export         diskinit
+        .import         opencmdchannel, closecmdchannel
+        .import         writefndiskcmd, readdiskerror
+        .import         isdisk, fnunit, fncmd
+
+;------------------------------------------------------------------------------
+; diskinit
+
+.proc   diskinit
+
+; Save device
+
+        sta     fnunit
+
+; Check for disk device
+
+        tax
+        jsr     isdisk
+        bcc     open
+        lda     #9              ; "Ilegal device"
+        rts
+
+; Open channel
+
+open:   jsr     opencmdchannel
+        bne     done
+
+; Write command
+
+        lda     #'i'            ; Init command
+        sta     fncmd
+        jsr     writefndiskcmd
+        bne     close
+
+; Read error
+
+        ldx     fnunit
+        jsr     readdiskerror
+
+; Close channel
+
+close:  pha
+        ldx     fnunit
+        jsr     closecmdchannel
+        pla
+
+done:   rts
+
+.endproc