diff --git a/build/Makefile b/build/Makefile
index ea6438f..d48a978 100644
--- a/build/Makefile
+++ b/build/Makefile
@@ -78,8 +78,8 @@ coldboot.rim: $(COLDBOOT)
 	$(AS) -n -f list -o a.lst $(COLDBOOT)
 
 # Filesystem image
-image.fs: cmd others
-	$(MKFS) -k a.out proto
+image.fs: cmd others a.out chrtbl.out
+	$(MKFS) -k a.out -c chrtbl.out proto
 	$(FSCK) image.fs
 
 # Alternate filesystem image: . and .. but no dd
@@ -87,8 +87,20 @@ alt/image.fs: altcmd altothers
 	$(MKFS) -1 -2 -3 -o alt/image.fs -k alt/a.out alt/proto
 	$(FSCK) -3 alt/image.fs
 
+# character table: assemble output of cas.s
+chrtbl.out: cas.out ../src/other/chrtbl.s
+	$(AS) -f ptr --no-label-warnings -o chrtbl.out ../src/other/chrtbl.s cas.out
+
+# run cas.s under a7out: needs local file!
+cas.out: bin/cas ../src/sys/cas.in
+	rm -f cas.in
+	ln -s ../src/sys/cas.in .
+	$(A7OUT) bin/cas cas.out cas.in
+	rm -f cas.in
+
 clean:
 	rm -f boot.rim image.fs a.lst n.out a.out
+	rm -f cas cas.in cas.out chrtbl.out
 	rm -f alt/image.fs alt/a.out alt/a.lst
 	rm -rf $(BINDIR) $(TESTDIR) 
 	rm -rf $(BINARIES)
diff --git a/src/cmd/cas.cas b/src/cmd/cas.cas
deleted file mode 100644
index 1a0e6c5..0000000
--- a/src/cmd/cas.cas
+++ /dev/null
@@ -1,551 +0,0 @@
-:ca
-v
-af
-nl
-x
-hd
-v
-hi
-x
-mn
-r
-
-:cb
-x
-ga
-v
-gi
-ik
-kk
-mi
-ma
-aa
-ai
-ck
-ek
-gi
-x
-mn
-r
-
-:cc
-x
-kk
-v
-mi
-mc
-ka
-ca
-ac
-ai
-dl
-x
-mn
-r
-
-:cd
-v
-aa
-ai
-ck
-kk
-mi
-ma
-x
-mn
-r
-
-:ce
-x
-mk
-v
-ma
-aa
-ak
-x
-gh
-v
-ga
-x
-mn
-r
-
-:cf
-v
-aa
-ak
-x
-gh
-v
-ga
-x
-mn
-r
-
-:cg
-x
-gf
-v
-gk
-nk
-x
-kk
-v
-mi
-mc
-ka
-ca
-ac
-ai
-dl
-x
-mn
-r
-
-:ch
-x
-aa
-v
-na
-x
-gb
-v
-gk
-x
-ak
-v
-nk
-x
-mn
-r
-
-:ci
-x
-md
-v
-mi
-x
-lf
-v
-af
-x
-ad
-v
-ai
-x
-mn
-r
-
-:cj
-x
-ka
-v
-mc
-mg
-ki
-ai
-x
-ag
-v
-al
-x
-mn
-r
-
-:ck
-x
-aa
-v
-na
-x
-ak
-v
-ia
-x
-mk
-v
-fe
-x
-mn
-r
-
-:cl
-x
-aa
-v
-ma
-mk
-x
-mn
-r
-
-:cm
-v
-aa
-hf
-ak
-nk
-x
-mn
-r
-
-:cn
-x
-ak
-v
-mk
-aa
-na
-x
-mn
-r
-
-:co
-x
-ai
-v
-ch
-ei
-ck
-ai
-ac
-ca
-ka
-mc
-mi
-kk
-ck
-x
-mn
-r
-
-:cp
-v
-aa
-ai
-ck
-ek
-gi
-ga
-x
-mn
-r
-
-:cq
-x
-mc
-v
-ka
-ca
-ac
-ai
-ck
-kk
-mi
-mc
-x
-jh
-v
-nl
-x
-mn
-r
-
-:cr
-v
-aa
-ai
-ck
-ek
-gi
-ga
-x
-mk
-v
-gf
-x
-mn
-r
-
-:cs
-x
-ka
-v
-mc
-mi
-kk
-ik
-gi
-gc
-ea
-ca
-ac
-ai
-dl
-x
-mn
-r
-
-:ct
-x
-aa
-v
-al
-x
-mf
-v
-af
-x
-mn
-r
-
-:cu
-x
-aa
-v
-ka
-mc
-mi
-kk
-x
-ak
-v
-lk
-x
-mn
-r
-
-:cv
-x
-aa
-v
-mf
-x
-ak
-v
-mf
-x
-mn
-r
-
-:cw
-x
-aa
-v
-mc
-af
-x
-ak
-v
-mi
-af
-x
-mn
-r
-
-:cx
-v
-gf
-x
-ak
-v
-gf
-x
-aa
-v
-nl
-x
-mn
-r
-
-:cy
-x
-aa
-v
-if
-x
-ak
-v
-if
-nf
-x
-mn
-r
-
-:cz
-x
-aa
-v
-ak
-ma
-ml
-x
-mn
-r
-
-:c0
-x
-ck
-v
-ai
-ac
-ca
-ka
-mc
-mi
-kk
-ck
-x
-mn
-r
-
-:c1
-x
-ce
-v
-af
-mf
-x
-md
-v
-mi
-x
-mn
-r
-
-:c2
-x
-ca
-v
-ac
-ai
-ck
-ek
-gi
-gc
-ia
-ma
-ml
-x
-mn
-r
-
-:c3
-x
-aa
-v
-ak
-fe
-fi
-hk
-kk
-mi
-mc
-x
-ka
-v
-nd
-x
-mn
-r
-
-:c4
-x
-mh
-v
-ah
-ia
-il
-x
-mn
-r
-
-:c5
-x
-ak
-v
-aa
-fa
-fi
-hk
-kk
-mi
-mc
-x
-ka
-v
-nd
-x
-mn
-r
-
-:c6
-x
-ck
-v
-ai
-ac
-ca
-ka
-mc
-mi
-kk
-hk
-fi
-fc
-ha
-x
-mn
-r
-
-:c7
-x
-aa
-v
-ak
-nb
-x
-mn
-r
-
-:c8
-x
-gc
-v
-ea
-ca
-ac
-ai
-ck
-ek
-gi
-gc
-ia
-ka
-mc
-mi
-kk
-ik
-gi
-x
-mn
-r
-
-:c9
-x
-ka
-v
-mc
-mi
-kk
-ck
-ai
-ac
-ca
-fa
-hc
-hi
-fk
-x
-mn
-r
diff --git a/src/other/chrtbl.s b/src/other/chrtbl.s
new file mode 100644
index 0000000..38737a0
--- /dev/null
+++ b/src/other/chrtbl.s
@@ -0,0 +1,24 @@
+" PLB 2020-01-05
+" start of a file to assemble output of cas.s
+
+" base. maybe AFTER table??
+b:
+
+" 128-word dispatch table for ASCII
+
+null; null; null; null; null; null; null; null
+null; null; null; null; null; null; null; null
+null; null; null; null; null; null; null; null
+null; null; null; null; null; null; null; null
+space; excla; quote; number; dollar; percent; amper; accl
+lparn; rparn; aster; plus; comma; minus; period; sla
+c0; c1; c2; c3; c4; c5; c6; c7
+c8; c9; colon; semcln; less; equal; great; quest
+at; ca; cb; cc; cd; ce; cf; cg
+ch; ci; cj; ck; cl; cm; cn; co
+cp; cq; cr; cs; ct; cu; cv; cw
+cx; cy cz; lbk; bsla; rbk; cmflx; under
+accr; la; lb; lc; ld; le; lf; lg
+lh; li; lj; lk; ll; lm; ln; lo
+lp; lq; lr; ls; lt; lu; lv; lw
+lx; ly lz; lbr; or; rbr; tild; null
diff --git a/src/other/pbboot.s b/src/other/pbboot.s
index 12f1008..4b5dd16 100644
--- a/src/other/pbboot.s
+++ b/src/other/pbboot.s
@@ -9,25 +9,18 @@
    caf				" reset cpu
    dscs				" clear disk status
 
-" code from maksys (altered to read instead of write):
-   -3072; dslw
+" code orignally from maksys
+" altered to read full 4K (system + char table)
+" instead of write:
+   -4096; dslw
    cla; dslm
    lac track; alss 8; xor o300000; dsld
    lac o2000; dsls
    dssf; jmp .-1
    dsrs; spa; hlt
 
-   -1024; dslw
-   lac d3072; dslm
-   lac track; alss 8; xor o300110; dsld
-   lac o2000; dsls
-   dssf; jmp .-1
-   dsrs; spa; hlt
-
    jmp 0100
 
 o2000: 02000
-d3072: 3072
 o300000: 0300000
-o300110: 0300110
 track: 0		" get 0-9 from switches!!!
diff --git a/src/cmd/scope.cas b/src/sys/cas.in
similarity index 61%
rename from src/cmd/scope.cas
rename to src/sys/cas.in
index c2a1f22..1f641f1 100644
--- a/src/cmd/scope.cas
+++ b/src/sys/cas.in
@@ -1,3 +1,554 @@
+:ca
+v
+af
+nl
+x
+hd
+v
+hi
+x
+mn
+r
+
+:cb
+x
+ga
+v
+gi
+ik
+kk
+mi
+ma
+aa
+ai
+ck
+ek
+gi
+x
+mn
+r
+
+:cc
+x
+kk
+v
+mi
+mc
+ka
+ca
+ac
+ai
+dl
+x
+mn
+r
+
+:cd
+v
+aa
+ai
+ck
+kk
+mi
+ma
+x
+mn
+r
+
+:ce
+x
+mk
+v
+ma
+aa
+ak
+x
+gh
+v
+ga
+x
+mn
+r
+
+:cf
+v
+aa
+ak
+x
+gh
+v
+ga
+x
+mn
+r
+
+:cg
+x
+gf
+v
+gk
+nk
+x
+kk
+v
+mi
+mc
+ka
+ca
+ac
+ai
+dl
+x
+mn
+r
+
+:ch
+x
+aa
+v
+na
+x
+gb
+v
+gk
+x
+ak
+v
+nk
+x
+mn
+r
+
+:ci
+x
+md
+v
+mi
+x
+lf
+v
+af
+x
+ad
+v
+ai
+x
+mn
+r
+
+:cj
+x
+ka
+v
+mc
+mg
+ki
+ai
+x
+ag
+v
+al
+x
+mn
+r
+
+:ck
+x
+aa
+v
+na
+x
+ak
+v
+ia
+x
+mk
+v
+fe
+x
+mn
+r
+
+:cl
+x
+aa
+v
+ma
+mk
+x
+mn
+r
+
+:cm
+v
+aa
+hf
+ak
+nk
+x
+mn
+r
+
+:cn
+x
+ak
+v
+mk
+aa
+na
+x
+mn
+r
+
+:co
+x
+ai
+v
+ch
+ei
+ck
+ai
+ac
+ca
+ka
+mc
+mi
+kk
+ck
+x
+mn
+r
+
+:cp
+v
+aa
+ai
+ck
+ek
+gi
+ga
+x
+mn
+r
+
+:cq
+x
+mc
+v
+ka
+ca
+ac
+ai
+ck
+kk
+mi
+mc
+x
+jh
+v
+nl
+x
+mn
+r
+
+:cr
+v
+aa
+ai
+ck
+ek
+gi
+ga
+x
+mk
+v
+gf
+x
+mn
+r
+
+:cs
+x
+ka
+v
+mc
+mi
+kk
+ik
+gi
+gc
+ea
+ca
+ac
+ai
+dl
+x
+mn
+r
+
+:ct
+x
+aa
+v
+al
+x
+mf
+v
+af
+x
+mn
+r
+
+:cu
+x
+aa
+v
+ka
+mc
+mi
+kk
+x
+ak
+v
+lk
+x
+mn
+r
+
+:cv
+x
+aa
+v
+mf
+x
+ak
+v
+mf
+x
+mn
+r
+
+:cw
+x
+aa
+v
+mc
+af
+x
+ak
+v
+mi
+af
+x
+mn
+r
+
+:cx
+v
+gf
+x
+ak
+v
+gf
+x
+aa
+v
+nl
+x
+mn
+r
+
+:cy
+x
+aa
+v
+if
+x
+ak
+v
+if
+nf
+x
+mn
+r
+
+:cz
+x
+aa
+v
+ak
+ma
+ml
+x
+mn
+r
+
+:c0
+x
+ck
+v
+ai
+ac
+ca
+ka
+mc
+mi
+kk
+ck
+x
+mn
+r
+
+:c1
+x
+ce
+v
+af
+mf
+x
+md
+v
+mi
+x
+mn
+r
+
+:c2
+x
+ca
+v
+ac
+ai
+ck
+ek
+gi
+gc
+ia
+ma
+ml
+x
+mn
+r
+
+:c3
+x
+aa
+v
+ak
+fe
+fi
+hk
+kk
+mi
+mc
+x
+ka
+v
+nd
+x
+mn
+r
+
+:c4
+x
+mh
+v
+ah
+ia
+il
+x
+mn
+r
+
+:c5
+x
+ak
+v
+aa
+fa
+fi
+hk
+kk
+mi
+mc
+x
+ka
+v
+nd
+x
+mn
+r
+
+:c6
+x
+ck
+v
+ai
+ac
+ca
+ka
+mc
+mi
+kk
+hk
+fi
+fc
+ha
+x
+mn
+r
+
+:c7
+x
+aa
+v
+ak
+nb
+x
+mn
+r
+
+:c8
+x
+gc
+v
+ea
+ca
+ac
+ai
+ck
+ek
+gi
+gc
+ia
+ka
+mc
+mi
+kk
+ik
+gi
+x
+mn
+r
+
+:c9
+x
+ka
+v
+mc
+mi
+kk
+ck
+ai
+ac
+ca
+fa
+hc
+hi
+fk
+x
+mn
+r
 :la
 x
 fb
diff --git a/src/sys/maksys.s b/src/sys/maksys.s
index 967e851..2367a09 100644
--- a/src/sys/maksys.s
+++ b/src/sys/maksys.s
@@ -15,14 +15,14 @@
    jmp error
 
    dscs
-   -3072; dslw
-   lac bufp; dslm
+   -3072; dslw			// word count: 3K
+   lac bufp; dslm		// transfer from buf
    lac track; alss 8; xor o300000; dsld
    lac o3000; dsls
    dssf; jmp .-1
    dsrs; spa; jmp error
-   -1024; dslw
-   lac d3072; dslm
+   -1024; dslw			// word count: 1K
+   lac d3072; dslm		// transfer from 3K mark (06000)
    lac track; alss 8; xor o300110; dsld
    lac o3000; dsls
    dssf; jmp .-1
diff --git a/tools/mkfs7 b/tools/mkfs7
index 12782b2..d90bbf4 100755
--- a/tools/mkfs7
+++ b/tools/mkfs7
@@ -675,7 +675,7 @@ sub usage {
 
 ### MAIN PROGRAM
 
-my ( $format, $output, $kernelfile ) = ( "simh", "image.fs" );
+my ( $format, $output, $kernelfile, $chartable ) = ( "simh", "image.fs" );
 
 GetOptions(
     'debug|d'    => \$debug,
@@ -685,6 +685,7 @@ GetOptions(
     'format|f=s' => \$format,
     'output|o=s' => \$output,
     'kernel|k=s' => \$kernelfile,
+    'chars|c=s'  => \$chartable,
 ) or usage();
 
 usage() if ( @ARGV < 1 );
@@ -696,10 +697,21 @@ dprint("\n");
 
 # If we were given a kernel image, write that to track 80
 # which is block number 6400.
+# (maksys.s can write to tracks 80-89)
+my $bootblock = 6400;
 if ($kernelfile) {
     dprint("Adding kernel $kernelfile to track 80\n");
     my @buf= read_file($kernelfile);
-    write_file(6400, @buf);
+    write_file($bootblock, @buf);
+}
+# If we were given a character table, write that
+# so it gets loaded at the 3K mark
+# maksys.s writes the contents of memory at 3K to the boot track!
+if ($chartable) {
+    dprint("Adding character table $chartable to track 80\n");
+    my @buf= read_file($chartable);
+    # XXX truncate to 1K, or at least complain??
+    write_file($bootblock + 3072/WORDSPERBLK, @buf);
 }
 dump_image( $format, $output );
 exit(0);