BSD 4_1_snap development

Work on file sys/mdec/tstoggle.s

Synthesized-from: CSRG/cd1/4.1.snap

diff --git a/sys/mdec/tstoggle.s b/sys/mdec/tstoggle.s
new file mode 100644 (file)
index 0000000..89ae9e6
--- /dev/null
+++ b/sys/mdec/tstoggle.s
@@ -0,0 +1,31 @@
+/*
+ * Prototype toggle in bootstrap code for ts type tapes.
+ * If on anything but a 780 with the drive on uba0
+ * this will have to be repaired by patching uba and umem.
+ */
+       .set    UBA0,0x20006000
+       .set    UMEM0,0x2013e000
+       .set    UBA_MAP,0x800
+       .set    TSADDR,0772520-0760000
+
+start:
+       movl    uba,r10
+       movl    mrv,UBA_MAP(r10)
+       addl3   mrv,$1,UBA_MAP+4(r10)
+       addl3   umem,$TSADDR,r11
+       clrw    2(r11)
+1:     tstb    2(r11)
+       bgeq    1b
+       movw    $0x200+setchr,(r11)
+1:     tstb    2(r11)
+       bgeq    1b
+       movw    $0x200+read,(r11)
+       halt
+       .align  2
+uba:   .long   UBA0
+umem:  .long   UMEM0
+mrv:   .long   0x80000000
+setchr:        .word   0xc004,0x200+char,0,0x8 # set characteristics command
+char:  .word   0x200+status,0,0xe,0    # characteristics
+read:  .word   0xc001,0,0,0x200        # read command
+status: