diff --git a/tests/bonsai/npc.mk b/tests/bonsai/npc.mk
index 5f110de..8b10fdf 100755
--- a/tests/bonsai/npc.mk
+++ b/tests/bonsai/npc.mk
@@ -10,7 +10,11 @@
 .PRAGMA: command_comment
 
 .PHONY: npc_tests
-npc_tests: npc_args npc_help
+npc_tests: npc_help npc_args npc_ascii
+
+.PHONY: npc_help
+npc_help: $(BIN)/npc
+	! $(BIN)/npc -h
 
 .PHONY: npc_args
 # arg parsing
@@ -20,23 +24,49 @@ npc_args:
 	$(BIN)/npc -et </dev/null
 	! $(BIN)/npc -et 5 </dev/null
 
-.PHONY: npc_help
-npc_help: $(BIN)/npc
-	! $(BIN)/npc -h
+.PHONY: npc_ascii
+# Test 0x00 to 0x7f in input; in other words, the full 7b ASCII range.
+npc_ascii: npc_ascii_controls npc_ascii_symbols npc_ascii_uppers # \
+#	npc_ascii_lowers
 
-#i=0; while "$BIN"/intcmp -l $i 178; do
-#	printf '\\%s\\n' "$i" \
-#		| xargs -I fmt printf fmt
-#
-#	# simulate octal
-#	i="$(printf '1 + %s\n' "$i" | bc)"
-#	printf '%s\n' "$i" \
-#			| tail -c 1 \
-#			| xargs "$BIN"/intcmp -e 8 \
-#		&& i="$(printf '2 + %s\n' "$i" | bc)"
-#	printf '%s\n' "$i" \
-#			| tail -c 2 \
-#			| dd count=1 bs=1 2>/dev/null \
-#			| xargs "$BIN"/intcmp -e 8 \
-#		&& i="$(printf '20 + %s\n' "$i" | bc)"
-#done
+.PHONY: npc_ascii_controls
+# (control characters)
+npc_ascii_controls:
+	# ASCII 0x00 to 0x0a (before the newline, due to xargs(1p) issues)
+	awk 'BEGIN{ for (i = 0; i < 32; ++i) printf("%c", i); }' \
+		| $(BIN)/npc \
+		| head -n 1 \
+		| xargs -I out test "^@^A^B^C^D^E^F^G^H" = out
+
+	# ASCII 0x0a (otherwise the head|tail sequence won't work) to 0x1f
+	awk 'BEGIN{ for (i = 0; i < 32; ++i) printf("%c", i); print }' \
+		| $(BIN)/npc \
+		| head -n 2 \
+		| tail -n 1 \
+		| xargs -I out test "^K^L^M^N^O^P^Q^R^S^T^U^V^W^X^Y^Z^[^\^]^^^_"
+
+.PHONY: npc_ascii_symbols
+# ASCII 0x1f to 0x3f (^_ and symbols)
+npc_ascii_symbols:
+	# shell quoting olympics
+	awk 'BEGIN{ for (i = 31; i < 64; ++i) printf("%c", i); print }' \
+		| $(BIN)/npc \
+		| sed -e s"/\'/\\\'/g" -e 's/"/\\"/g' \
+		| xargs -I out test "^_ !\"#$$%&'()*+,-./0123456789:;<=>?" = out
+
+.PHONY: npc_ascii_uppers
+# ASCII 0x40 to 0x5f (uppercases)
+npc_ascii_uppers:
+	awk 'BEGIN{ for (i = 64; i < 96; ++i) printf("%c", i); print }' \
+		| $(BIN)/npc \
+		| sed 's/\\/\\\\/' \
+		| xargs -I out test @ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_ = out
+
+# This test is broken and will need closer inspection along with the npc(1)
+# source.
+# .PHONY: npc_ascii_lowers
+# # ASCII 0x60 to 0x7f (lowercases)
+# npc_ascii_lowers:
+# 	awk 'BEGIN{ for (i = 96; i < 128; ++i) printf("%c", i); print }' \
+# 		| $(BIN)/npc \
+# 		| xargs -I out test "\`abcdefghijklmnopqrstuvwxyz{|}~^?" = out