diff --git a/Makefile b/Makefile
index fb7cd8a2d..27c571ad9 100644
--- a/Makefile
+++ b/Makefile
@@ -23,6 +23,23 @@ else
   PATHSEP=\\#
 endif
 
+ifeq ($(PLATFORM),)
+  -include Makefile.platform
+  ifeq ($(PLATFORM),)
+    PLATFORM=PM3RDV4
+  else
+    ${info using saved PLATFORM '$(PLATFORM)'}
+  endif
+endif
+
+include common/Makefile.hal
+
+$(info ===================================================================)
+$(info PLATFORM: $(PLATFORM))
+$(info $(PLTNAME))
+$(info Included supports: $(PLATFORM_DEFS))
+$(info ===================================================================)
+
 all clean: %: client/% bootrom/% armsrc/% recovery/% mfkey/% nonce2key/%
 
 mfkey/%: FORCE
diff --git a/armsrc/Makefile b/armsrc/Makefile
index 7e948293a..382407e1d 100644
--- a/armsrc/Makefile
+++ b/armsrc/Makefile
@@ -8,10 +8,27 @@
 
 APP_INCLUDES = apps.h
 
+# This Makefile might have been called directly, not via the root Makefile, so:
+ifeq ($(PLTNAME),)
+  -include ../Makefile.platform
+  ifeq ($(PLATFORM),)
+    PLATFORM=PM3RDV4
+  else
+    ${info using saved PLATFORM '$(PLATFORM)'}
+  endif
+  include ../common/Makefile.hal
+  $(info ===================================================================)
+  $(info PLATFORM: $(PLATFORM))
+  $(info $(PLTNAME))
+  $(info Included supports: $(PLATFORM_DEFS))
+  $(info ===================================================================)
+endif
+
 #remove one of the following defines and comment out the relevant line
 #in the next section to remove that particular feature from compilation.
 # NO space,TABs after the "\" sign.
-APP_CFLAGS = -DWITH_CRC \
+APP_CFLAGS = $(PLATFORM_DEFS) \
+			 -DWITH_CRC \
 			 -DON_DEVICE \
 			 -DWITH_LF \
 			 -DWITH_HITAG \
@@ -21,8 +38,6 @@ APP_CFLAGS = -DWITH_CRC \
 			 -DWITH_ISO14443a \
 			 -DWITH_ICLASS \
 			 -DWITH_FELICA \
- 			 -DWITH_FLASH \
-			 -DWITH_SMARTCARD \
 			 -DWITH_HFSNOOP \
 			 -DWITH_LF_SAMYRUN \
 			 -fno-strict-aliasing -ffunction-sections -fdata-sections
diff --git a/client/Makefile b/client/Makefile
index c7a3df7b6..ec12dedca 100644
--- a/client/Makefile
+++ b/client/Makefile
@@ -4,6 +4,22 @@
 # the license.
 #-----------------------------------------------------------------------------
 
+# This Makefile might have been called directly, not via the root Makefile, so:
+ifeq ($(PLTNAME),)
+  -include ../Makefile.platform
+  ifeq ($(PLATFORM),)
+    PLATFORM=PM3RDV4
+  else
+    ${info using saved PLATFORM '$(PLATFORM)'}
+  endif
+  include ../common/Makefile.hal
+  $(info ===================================================================)
+  $(info PLATFORM: $(PLATFORM))
+  $(info $(PLTNAME))
+  $(info Included supports: $(PLATFORM_DEFS))
+  $(info ===================================================================)
+endif
+
 # reveng will compile without macros, but these may be useful:
 # Add -DBMPMACRO to use bitmap size constant macros (edit config.h)
 # Add -DNOFORCE  to disable the -F switch
@@ -90,8 +106,7 @@ else
     QTGUIOBJS = $(OBJDIR)/guidummy.o
 endif
 
-# RDV40 flag enables flashmemory commands in client.  comment out if you don't have rdv40
-CFLAGS += -DWITH_FLASH -DWITH_SMARTCARD
+CFLAGS += $(PLATFORM_DEFS)
 
 # Flags to generate temporary dependency files
 DEPFLAGS = -MT $@ -MMD -MP -MF $(OBJDIR)/$*.Td
diff --git a/common/Makefile.common b/common/Makefile.common
index 59ac01f29..bfbfc0a80 100644
--- a/common/Makefile.common
+++ b/common/Makefile.common
@@ -21,13 +21,13 @@ platform = $(shell uname)
 all:
 
 CROSS  ?= arm-none-eabi-
-CC	= $(CROSS)gcc
-AS	= $(CROSS)as
-LD	= $(CROSS)ld
+CC = $(CROSS)gcc
+AS = $(CROSS)as
+LD = $(CROSS)ld
 OBJCOPY = $(CROSS)objcopy
 GZIP=gzip
 
-OBJDIR	= obj
+OBJDIR = obj
 
 INCLUDE = -I../include -I../common -I.
 
diff --git a/common/Makefile.hal b/common/Makefile.hal
new file mode 100644
index 000000000..e34095f2d
--- /dev/null
+++ b/common/Makefile.hal
@@ -0,0 +1,56 @@
+define KNOWN_PLATFORMS
+
++--------------------------------------------------------+
+| PLATFORM      | DESCRIPTION                            |
++--------------------------------------------------------+
+| PM3RDV4 (def) | Proxmark3 rdv4      with AT91SAM7S512  |
++--------------------------------------------------------+
+| PM3EVO        | Proxmark3 EVO       with AT91SAM7S512  |
++--------------------------------------------------------+
+| PM3EASY       | Proxmark3 rdv3 Easy with AT91SAM7S256  |
++--------------------------------------------------------+
+| PM3RDV2       | Proxmark3 rdv2      with AT91SAM7S512  |
++--------------------------------------------------------+
+| PM3OLD256     | Proxmark3 V1        with AT91SAM7S256  |
++--------------------------------------------------------+
+| PM3OLD512     | Proxmark3 V1        with AT91SAM7S512  |
++--------------------------------------------------------+
+
+Options to define platform:
+(1) Run make with PLATFORM specified as follows:
+make PLATFORM=PM3EASY
+
+(2) Save a file called Makefile.platform with contents:
+PLATFORM=PM3EASY
+
+endef
+
+PLTNAME = Unknown Platform
+
+ifeq ($(PLATFORM),PM3RDV4)
+  MCU = AT91SAM7S512
+  PLATFORM_DEFS = -DWITH_SMARTCARD -DWITH_FLASH
+  PLTNAME = Proxmark3 rdv4
+else ifeq ($(PLATFORM),PM3EVO)
+  MCU = AT91SAM7S512
+  PLTNAME = Proxmark3 EVO
+else ifeq ($(PLATFORM),PM3EASY)
+  MCU = AT91SAM7S256
+  PLTNAME = Proxmark3 rdv3 Easy
+else ifeq ($(PLATFORM),PM3RDV2)
+  MCU = AT91SAM7S512
+  PLTNAME = Proxmark3 rdv2
+else ifeq ($(PLATFORM),PM3OLD256)
+  MCU = AT91SAM7S256
+  PLTNAME = Proxmark3 V1 with AT91SAM7S256
+else ifeq ($(PLATFORM),PM3OLD512)
+  MCU = AT91SAM7S512
+  PLTNAME = Proxmark3 V1 with AT91SAM7S512
+else
+  $(error Invalid or empty PLATFORM: $(PLATFORM). Known platforms: $(KNOWN_PLATFORMS))
+endif
+
+export PLATFORM
+export PLTNAME
+export MCU
+export PLATFORM_DEFS