diff --git a/.travis.yml b/.travis.yml
index 49d9371..8925d95 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,7 +12,7 @@ matrix:
   include:
     - env: RASPPI=0
     - env: RASPPI=1
-    - env: RASPPI=1+
+    - env: RASPPI=1Plus
     - env: RASPPI=2 
     - env: RASPPI=3
 
diff --git a/Makefile.rules b/Makefile.rules
index da1cb8c..38dd4c3 100644
--- a/Makefile.rules
+++ b/Makefile.rules
@@ -3,6 +3,9 @@ ifneq ($(V),1)
 Q		:= @
 endif
 
+#use RASPPI = 1 Raspberry 1B (26 IOports)
+#use RASPPI = 1Plus to Raspberry 1B+ (40 I/OPorts)
+
 RASPPI	?= 3
 PREFIX	?= arm-none-eabi-
 
@@ -12,17 +15,14 @@ AS	= $(CC)
 LD	= $(PREFIX)ld
 AR	= $(PREFIX)ar
 
-#Changed RASPPI = 1 to Raspberry 1B (26 IOports) 		A.Buch 02.Jan. 2020
-#Added	RASPPI = 1+ to Rasüberry 1B+ (40 I/OPorts)
-
 ifeq ($(strip $(RASPPI)),0)
 ARCH	?= -march=armv6zk -mtune=arm1176jzf-s -mfpu=vfp -mfloat-abi=hard -DRPIZERO=1 -DEXPERIMENTALZERO=1
 CFLAGS	+= -DRPIZERO=1 -DRASPPI=1
 else ifeq ($(strip $(RASPPI)),1)
 ARCH	?= -march=armv6zk -mtune=arm1176jzf-s -mfpu=vfp -mfloat-abi=hard -DEXPERIMENTALZERO=1
 CFLAGS	+= -DRASPPI=1
-else ifeq ($(strip $(RASPPI)),1+)
-ARCH	?= -march=armv6zk -mtune=arm1176jzf-s -mfpu=vfp -mfloat-abi=hard -DRPIBPLUS=1
+else ifeq ($(strip $(RASPPI)),1Plus)
+ARCH	?= -march=armv6zk -mtune=arm1176jzf-s -mfpu=vfp -mfloat-abi=hard -DRPIBPLUS=1 -DEXPERIMENTALZERO=1
 CFLAGS	+= -DRPIBPLUS=1 -DRASPPI=1
 else ifeq ($(strip $(RASPPI)),2)
 ARCH	?= -march=armv7-a -mtune=cortex-a7 -mfpu=neon-vfpv4 -mfloat-abi=hard -marm -DRPI2=1 -DEXPERIMENTALZERO=1
@@ -31,7 +31,7 @@ else ifeq ($(strip $(RASPPI)),3)
 ARCH	?= -march=armv8-a+crc -mtune=cortex-a53 -mfpu=crypto-neon-fp-armv8 -mfloat-abi=hard -marm -DRPI3=1
 CFLAGS	+= -DRPI3=1
 else
-$(error RASPPI must be one of: 0, 1, 1+, 2, 3)
+$(error RASPPI must be one of: 0, 1, 1Plus, 2, 3)
 endif
 
 AFLAGS	 += $(ARCH)