add mcodes bootw11,noboot; add ram:&noboot

tools/mcode/sys/README.md

@@ -3,3 +3,4 @@ This directory tree contains **system codes** and contains
 | File | Docu | Comments |
 | --------- | --------- | ------- |
 | [blink.mac](blink.mac) | - | _blinking lights_ demo |
+| [noboot.mac](noboot.mac) | - | boot blocker (for disk block 0) |

tools/mcode/sys/noboot.mac

@@ -0,0 +1,35 @@
+; $Id: noboot.mac 1143 2019-05-01 13:25:51Z mueller $
+; Copyright 2019- by Walter F.J. Mueller <W.F.J.Mueller@gsi.de>
+; License disclaimer see License.txt in $RETROBASE directory
+;
+; Boot blocker, when loaded and started at 0, writes
+;    This is not a hardware bootable disk
+;
+        .include  |lib/defs_dl.mac|
+;
+        CR = 015
+        LF = 012
+;
+; starts at 0 !
+;
+        .asect
+        . = 0
+;
+start:  mov     #text, r0
+1$:     tstb    (r0)
+        beq     3$
+2$:     tstb    @#to.csr
+        bpl     2$
+        movb    (r0)+,@#to.buf
+        br      1$
+3$:     halt
+;
+text:   .ascii  <CR><LF>
+        .ascii /++======================================++/<CR><LF>
+        .ascii /|| This is not a hardware bootable disk ||/<CR><LF>
+        .ascii /++======================================++/<CR><LF>
+        .ascii <CR><LF>
+        .ascii /CPU WILL HALT/<CR><LF>
+        .asciz <CR><LF>
+;
+        .end    start