diff --git a/tests/Makefile b/tests/Makefile
new file mode 100644
index 0000000..2b28e60
--- /dev/null
+++ b/tests/Makefile
@@ -0,0 +1,10 @@
+
+SUBDIRS = basic diags 
+
+define makeone
+	echo "[ $(1) ]";
+	make -C $(1) $(2);
+endef
+
+all clean:
+	@$(foreach dir,$(SUBDIRS),$(call makeone,$(dir),$@))
diff --git a/tests/NOTES.txt b/tests/NOTES.txt
new file mode 100644
index 0000000..52153c9
--- /dev/null
+++ b/tests/NOTES.txt
@@ -0,0 +1,43 @@
+MAINDEC
+
+801-2C           8/30/65        JMS & JMP test                               1x
+801-1 RIM        5/ 4/65        Instruction test - part 1                    1x
+802-2B BIN       3/22/66        Instruction test - part 2b                   1x
+
+8E-D1EB-PB       5/ 1/68        PDP-8, 8I Extended memory                    1x
+
+08-D1GD-PB       7/27/70        PDP-8, 8I, 8S Extended memory control        1x
+08-D1HA-PB      10/ 1/68        PDP-8, 8I extended memory address test       1x
+
+8I-D01B-PB       3/25/68        Instruction test 1                           1x
+8I-D02B-PB       3/25/68        Instruction test 2                           1x
+8I-D02B-PB       1/ 3/68        Instruction test 2b                          1x
+8I-D02B-PB       1/ 3/68        Instruction test 2b                          1x
+
+---
+
+http://pdp-8.org/papertape/MAINDEC-08-D1EB-PB.pt
+http://pdp-8.org/papertape/MAINDEC-08-D1GD-PB.pt
+http://pdp-8.org/papertape/MAINDEC-08-D1HA-PB.pt
+
+http://pdp-8.org/papertape/MAINDEC-8I-D01C-PB.pt	x
+http://pdp-8.org/papertape/MAINDEC-8I-D02B-PB.pt	x
+
+http://pdp-8.org/papertape/MAINDEX-08-D1GB-PB.pt	x
+
+---
+
+     MAINDEX-08-D1GB-PB   5/5/68
+     PDP 8I,8,8/S
+     EXTENDED MEMORY CONTROL TEST
+
+     Maindec-8I-DO1C-Pb  12/10/69		x
+     Instruction Test 1
+     Dec Copyright December 1969
+
+     MAINDEC-8I-DO2B-PB     3/21/68		x
+     Instruction Test 2
+
+     MAINDEX-08-DO2B-PB   1/3/68		x
+     INSTRUCTION TEST - PART 2B
+
diff --git a/tests/basic/Makefile b/tests/basic/Makefile
new file mode 100644
index 0000000..ed536d1
--- /dev/null
+++ b/tests/basic/Makefile
@@ -0,0 +1,3 @@
+#
+
+all:
diff --git a/tests/bin/MAINDEC-08-D1EB-PB.pt b/tests/bin/MAINDEC-08-D1EB-PB.pt
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diff --git a/tests/bin/MAINDEC-8I-D01C-PB.pt.fixed b/tests/bin/MAINDEC-8I-D01C-PB.pt.fixed
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diff --git a/tests/bin/MAINDEC-8I-D02B-PB.pt b/tests/bin/MAINDEC-8I-D02B-PB.pt
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diff --git a/tests/bin/MAINDEX-08-D1GB-PB.pt b/tests/bin/MAINDEX-08-D1GB-PB.pt
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diff --git a/tests/bin/MAINDEX-08-D1GB-PB.pt.fixed b/tests/bin/MAINDEX-08-D1GB-PB.pt.fixed
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diff --git a/tests/bin/MAINDEX-08-D1GB.bin b/tests/bin/MAINDEX-08-D1GB.bin
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diff --git a/tests/diags/MAINDEC-8I-D01C.simh.script b/tests/diags/MAINDEC-8I-D01C.simh.script
new file mode 100644
index 0000000..c5c06da
--- /dev/null
+++ b/tests/diags/MAINDEC-8I-D01C.simh.script
@@ -0,0 +1,4 @@
+load ../bin/MAINDEC-8I-D01C-PB.pt.fixed
+d SR 07777
+run 0200
+quit
diff --git a/tests/diags/MAINDEC-8I-D02B.simh.script b/tests/diags/MAINDEC-8I-D02B.simh.script
new file mode 100644
index 0000000..f7317b0
--- /dev/null
+++ b/tests/diags/MAINDEC-8I-D02B.simh.script
@@ -0,0 +1,4 @@
+load ../bin/MAINDEC-8I-D02B-PB.pt.fixed
+d SR 0
+run 0200
+quit
diff --git a/tests/diags/MAINDEX-08-D1GB.simh.script b/tests/diags/MAINDEX-08-D1GB.simh.script
new file mode 100644
index 0000000..f622242
--- /dev/null
+++ b/tests/diags/MAINDEX-08-D1GB.simh.script
@@ -0,0 +1,5 @@
+load ../bin/MAINDEX-08-D1GB-PB.pt.fixed
+d SR 017
+run 0200
+quit
+
diff --git a/tests/diags/Makefile b/tests/diags/Makefile
new file mode 100644
index 0000000..6066ef7
--- /dev/null
+++ b/tests/diags/Makefile
@@ -0,0 +1,47 @@
+#
+# make "mem" files for simulation from various binary formats
+# we get to xxdp and other places.
+#
+
+SIMH_PDP8 = ../../simhv36-1/BIN/pdp8
+
+DIAGS = MAINDEX-08-D1GB MAINDEC-8I-D01C MAINDEC-8I-D02B 
+#MAINDEC-08-D1GD MAINDEC-08-D1EB MAINDEC-08-D1HA
+
+MEMS = $(addsuffix .mem,$(basename $(DIAGS)))
+LOGS = $(addsuffix .log,$(basename $(DIAGS)))
+
+#all: loadtomem mems logs
+all: mems logs
+
+mems: $(MEMS)
+
+define loadone
+	../../utils/showbin/showbin -z $(1) >$(2);
+	../../utils/skipz/skipz $(1) >$(1).fixed;
+endef
+
+define genlog_from_script
+	M=10000 $(SIMH_PDP8) $(1) >$(2)
+endef
+
+#------------------------------
+
+%.mem: ../bin/%-PB.pt
+	$(call loadone,$<,$@)
+
+#------------------------------
+
+.PRECIOUS: $(LOGS)
+
+logs: $(LOGS)
+
+%.log : %.simh.script
+	$(call genlog_from_script,$<,$@)
+
+
+#------------------------------
+
+clean:
+	rm -rf *.mem *.log
+	rm -rf loadtomem
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