diff --git a/.circleci/config.yml b/.circleci/config.yml
index d628102..67afbf9 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -23,7 +23,9 @@ jobs:
           command: make tools_build
       - run:
           name: build SGDK
-          command: make sgdk_build
+          command: |
+              export GENDEV=`pwd`/build
+              make sgdk_build sgdk_install
       - run:
           name: build samples
           command: |
diff --git a/Dockerfile b/Dockerfile
index 487bf90..277b0b0 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -42,4 +42,4 @@ ENV PATH $GENDEV/bin:$PATH
 
 WORKDIR /src
 
-ENTRYPOINT make -f $GENDEV/sgdk/mkfiles/makefile.gen 
+ENTRYPOINT make -f $GENDEV/sgdk/mkfiles/Makefile.rom 
diff --git a/Makefile b/Makefile
index 324be8f..e9600ea 100644
--- a/Makefile
+++ b/Makefile
@@ -19,6 +19,9 @@ PATH := $(BUILDDIR)/bin:$(PATH)
 build: toolchain_build tools_build sgdk_build
 	echo "Done"
 
+docker_build:
+	docker build -t gendev .
+
 $(BUILDDIR):
 	mkdir -p $@
 
@@ -44,9 +47,6 @@ tools_build:
 tools_clean:
 	cd tools && $(MAKE) tools_clean
 
-sgdk_samples:
-	cd sgdk && $(MAKE) sample_clean samples
-
 $(GENDEV):
 	if [ -w /opt ]; then \
 		mkdir -p $(GENDEV); \
@@ -82,11 +82,17 @@ dist/gendev_$(VER)_all.deb: pkg_build
 	cd dist && dpkg-deb -Zxz -z9 --build $(TOPDIR)/pkg_build .
 
 sgdk_build:
-	cd sgdk && GENDEV=$(BUILDDIR) $(MAKE) install
+	cd sgdk && GENDEV=$(BUILDDIR) $(MAKE)
+
+sgdk_install: $(GENDEV)
+	cd sgdk && $(MAKE) install
 
 sgdk_clean:
 	- cd sgdk && $(MAKE) clean
 
+sgdk_samples:
+	cd sgdk && $(MAKE) sample_clean samples
+
 clean: tools_clean toolchain_clean sgdk_clean
 	-rm -rf $(BUILDDIR)
 	-rm -rf pkg_build
diff --git a/sgdk/Makefile b/sgdk/Makefile
index c5149eb..380319b 100644
--- a/sgdk/Makefile
+++ b/sgdk/Makefile
@@ -1,59 +1,97 @@
+
+# Locatin of gendev install
 GENDEV?=/opt/gendev/
 GENBIN=$(GENDEV)/bin
-GENGCC_BIN=$(GENDEV)/bin
-SGDKDIR=$(CURDIR)/SGDK
+
+# Location of build and source
+BUILDDIR?=$(CURDIR)/build
+SGDKDIR=$(BUILDDIR)/sgdk
 SAMPLESDIR=$(SGDKDIR)/sample
 
-SGDKVER=v1.51
+# Version of SGDK to build
+SGDKVER=v1.62
+
+# SGDK install location
 SGDKINSTALLDIR=$(GENDEV)/sgdk$(SGDKVER)
 
-all: tools $(SGDKDIR) $(SGDKDIR)/libmd.a
+all: $(SGDKDIR) $(SGDKDIR)/lib/libmd.a tools
 
-tools: $(SGDKDIR)
+# Various tools needed to use SGDK
+tools: $(SGDKDIR) $(SGDKINSTALLDIR)
+	cd $(SGDKDIR)/tools/bintos/src && \
+	gcc -o bintos bintos.c
+	cd $(SGDKDIR)/tools/sizebnd/src && \
+	gcc -o sizebnd sizebnd.c
+	cd $(SGDKDIR)/tools/xgmtool && \
+		$(MAKE) -f $(CURDIR)/mkfiles/Makefile.xgmtool
 	cd $(SGDKDIR)/tools/bintos/src && \
-	gcc -o bintos bintos.c  && cp bintos $(GENDEV)/bin/.
+		cp bintos $(SGDKINSTALLDIR)/bin/.
 	cd $(SGDKDIR)/tools/sizebnd/src && \
-	gcc -o sizebnd sizebnd.c  && cp sizebnd $(GENDEV)/bin/.
+		cp sizebnd $(SGDKINSTALLDIR)/bin/.
 	cd $(SGDKDIR)/tools/xgmtool && \
-		$(MAKE) -f ../../../files/Makefile.xgmtool && cp out/xgmtool $(GENDEV)/bin/.
-	cp $(SGDKDIR)/bin/*.jar $(GENDEV)/bin/.
+		cp out/xgmtool $(SGDKINSTALLDIR)/bin/.
+	cp $(SGDKDIR)/bin/*.jar $(SGDKINSTALLDIR)/bin/.
 
+
+# Create a new patchfile based on the current SGDK checkout
 patch: $(SGDKDIR)
-	cd $(SGDKDIR) && git diff . > ../files/sgdk_$(SGDKVER).diff
+	cd $(SGDKDIR) && git diff . > $(CURDIR)/patches/sgdk_$(SGDKVER).diff
 
+# Update an SGDK checkout with the current versions patchfile
 prep: $(SGDKDIR)
-	cd $(SGDKDIR) && patch -u -p1 -l < ../files/sgdk_$(SGDKVER).diff
+	cd $(SGDKDIR) && patch -u -p1 -l < $(CURDIR)/patches/sgdk_$(SGDKVER).diff
+
+$(BUILDDIR):
+	mkdir -p $@
 
+# Checkout and prep SGDK for building
 SGDK: $(SGDKDIR)
-$(SGDKDIR):
-	git clone -b '$(SGDKVER)' --single-branch --depth 1 https://github.com/Stephane-D/SGDK.git
+$(SGDKDIR): $(BUILDDIR)
+	cd $(BUILDDIR) && git clone -b '$(SGDKVER)' --single-branch --depth 1 https://github.com/Stephane-D/SGDK.git sgdk
+	cd $(SGDKDIR) && patch -u -p1 -l < $(CURDIR)/patches/sgdk_$(SGDKVER).diff
+	rm -f $(SGDKDIR)/lib/*.a
+	rm -f $(SGDKDIR)/bin/*.exe
 
-$(SGDKDIR)/libmd.a: prep
-	cp -rf ../tools/files/applib/lib $(SGDKDIR)/tools/appack
-	cd $(SGDKDIR) && ln -sf ../files/Makefile.sgdk_lib .
-	cd $(SGDKDIR) && $(MAKE) -f Makefile.sgdk_lib
+$(SGDKDIR)/mkfiles: $(SGDKDIR)
+	mkdir -p $(SGDKDIR)/mkfiles
+	cp -f $(CURDIR)/mkfiles/makefile.vars $@/.
+	cp -f $(CURDIR)/mkfiles/Makefile.sgdk_lib $@/.
+	cp -f $(CURDIR)/mkfiles/Makefile.rom $@/.
+
+$(SGDKDIR)/lib/libmd.a: $(SGDKDIR) $(SGDKDIR)/mkfiles tools
+	cd $(SGDKDIR) && SGDKDIR=$(SGDKDIR) $(MAKE) -f $(CURDIR)/mkfiles/Makefile.sgdk_lib
+	cp $(GENDEV)/lib/libgcc.a $(SGDKDIR)/lib/libgcc.a
+	mv $(SGDKDIR)/libmd.a $(SGDKDIR)/lib/libmd.a
+	@echo "Done building sgdk library"	
 
 $(SGDKINSTALLDIR):
 	mkdir -p $@
 	rm -f $(GENDEV)/sgdk
 	cd $(GENDEV) && ln -sf sgdk$(SGDKVER) sgdk
+	mkdir -p $@/src
+	mkdir -p $@/bin
+	mkdir -p $@/inc
+	mkdir -p $@/res
+	mkdir -p $@/lib
+	mkdir -p $@/mkfiles
 
-install: tools $(SGDKDIR)/libmd.a $(SGDKINSTALLDIR)
+install: $(SGDKDIR)/lib/libmd.a $(SGDKINSTALLDIR)
 	echo "Install"
-	mkdir -p $(GENDEV)/sgdk/src
-	mkdir -p $(GENDEV)/sgdk/inc
-	mkdir -p $(GENDEV)/sgdk/lib
-	mkdir -p $(GENDEV)/sgdk/res
-	mkdir -p $(GENDEV)/sgdk/mkfiles
-	cp $(SGDKDIR)/md.ld $(GENDEV)/sgdk/.
-	cp $(SGDKDIR)/inc/* $(GENDEV)/sgdk/inc/.
-	cp -r $(SGDKDIR)/src/boot $(GENDEV)/sgdk/src/.
-	cp -r $(SGDKDIR)/res/* $(GENDEV)/sgdk/res/.
-	cp $(GENDEV)/lib/libgcc.a $(GENDEV)/sgdk/lib/.
-	cp $(SGDKDIR)/libmd.a $(GENDEV)/sgdk/lib/.
-	cp $(SGDKDIR)/makefile.gen $(GENDEV)/sgdk/mkfiles/.
-	cp files/makefile.vars $(GENDEV)/sgdk/mkfiles/.
-	cp $(SGDKDIR)/tools/sizebnd/src/sizebnd $(GENDEV)/bin/
+	cp $(SGDKDIR)/md.ld $(SGDKINSTALLDIR)/.
+	cp $(SGDKDIR)/inc/* $(SGDKINSTALLDIR)/inc/.
+	cp -r $(SGDKDIR)/src/boot $(SGDKINSTALLDIR)/src/.
+	cp -r $(SGDKDIR)/res/* $(SGDKINSTALLDIR)/res/.
+	cp $(GENDEV)/lib/libgcc.a $(SGDKINSTALLDIR)/lib/.
+	cp $(SGDKDIR)/lib/libmd.a $(SGDKINSTALLDIR)/lib/.
+	cp $(SGDKDIR)/makefile.gen $(SGDKINSTALLDIR)/mkfiles/.
+	cp $(SGDKDIR)/mkfiles/* $(SGDKINSTALLDIR)/mkfiles/.
+	cp $(SGDKDIR)/tools/sizebnd/src/sizebnd $(SGDKINSTALLDIR)/bin/
+	cd $(SGDKINSTALLDIR)/bin && ln -sf ../../bin/m68k-elf-gcc gcc
+	cd $(SGDKINSTALLDIR)/bin && ln -sf ../../bin/m68k-elf-nm nm
+	cd $(SGDKINSTALLDIR)/bin && ln -sf ../../bin/m68k-elf-ld ld
+	cd $(SGDKINSTALLDIR)/bin && ln -sf ../../bin/m68k-elf-objcopy objcopy
+	cd $(SGDKINSTALLDIR)/bin && ln -sf ../../bin/sjasm sjasm
+
 
 SAMPLES=$(wildcard $(SAMPLESDIR)/*/out)
 SAMPLEROMS=$(addsuffix /rom.bin,$(SAMPLES))
@@ -64,15 +102,16 @@ sample_clean: $(CLEANSAMPLES)
 	@echo "Done cleaning samples"
 
 $(CLEANSAMPLES):
-	cd $@/.. && $(MAKE) -f $(SGDKDIR)/makefile.gen clean
+	cd $@/.. && $(MAKE) -f $(CURDIR)/mkfiles/Makefile.rom clean
 
 samples: $(SAMPLEROMS)
 	@echo "All samples built"
 
-$(SAMPLEDIR)/%/out/rom.bin:
+$(SAMPLESDIR)/%/out/rom.bin:
 	echo "ROM $@"
-	cd $@/../../ && $(MAKE) -f $(GENDEV)/sgdk/mkfiles/makefile.gen
+	cd $@/../../ && GENDEV=$(GENDEV) $(MAKE) -f $(SGDKINSTALLDIR)/mkfiles/Makefile.rom
 
 clean:
 	echo "Clean"
 	-rm -rf $(SGDKDIR)
+	-rm -rf $(BUILDDIR)
diff --git a/sgdk/files/sgdk.ld b/sgdk/files/sgdk.ld
deleted file mode 100644
index 13c81f8..0000000
--- a/sgdk/files/sgdk.ld
+++ /dev/null
@@ -1,116 +0,0 @@
-OUTPUT_ARCH(m68k)
-SEARCH_DIR(.)
-/*GROUP(-lbcc -lc -lgcc)*/
-__DYNAMIC  =  0;
-
-/*
- * Setup the memory map of the SEGA Genesis.
- * stack grows down from high memory.
- *
- * The memory map look like this:
- * +--------------------+ <- low memory
- * | .text              |
- * |        _etext      |
- * |        ctor list   | the ctor and dtor lists are for
- * |        dtor list   | C++ support
- * +--------------------+
- * .                    .
- * .                    .
- * .                    .
- * +--------------------+ <- 0x00FF0000
- * | .data              | initialized data goes here
- * |        _data       | 
- * |        _edata      |
- * +--------------------+
- * | .bss               |
- * |        _bstart     | start of bss, cleared by crt0
- * |        _bend       | start of heap, used by sbrk()
- * +--------------------+
- * .                    .
- * .                    .
- * .                    .
- * |        __stack     | top of stack
- * +--------------------+ <- 0x01000000
- */
-MEMORY
-{
-	rom : ORIGIN = 0x00000000, LENGTH = 0x00400000
-	ram : ORIGIN = 0x00FF0000, LENGTH = 0x00010000
-}
-
-/*
- * allocate the stack to be at the top of memory, since the stack
- * grows down
- */
-
-PROVIDE (__stack = 0x01000000);
-
-
-SECTIONS
-{
-  .text 0x00000000:
-  {
-    *(.text .text.*)
-    . = ALIGN(0x4);
-     __CTOR_LIST__ = .;
-    LONG((__CTOR_END__ - __CTOR_LIST__) / 4 - 2)
-    *(.ctors)
-    LONG(0)
-    __CTOR_END__ = .;
-    __DTOR_LIST__ = .;
-    LONG((__DTOR_END__ - __DTOR_LIST__) / 4 - 2)
-    *(.dtors)
-     LONG(0)
-    __DTOR_END__ = .;
-    *(.rodata .rodata.*)
-    *(.gcc_except_table .gcc_except_table.*)
-
-    . = ALIGN(0x4);
-    __INIT_SECTION__ = . ;
-    *(.init)
-    SHORT (0x4E75)	/* rts */
-
-    __FINI_SECTION__ = . ;
-    *(.fini)
-    SHORT (0x4E75)	/* rts */
-
-    _etext = .;
-    *(.lit)
-  } > rom
-  _stext = SIZEOF (.text); 
-
-  .data 0xFF0000 :
-  AT ( ADDR (.text) + SIZEOF (.text) )
-  {
-    *(.got.plt) *(.got) 
-    *(.shdata)
-    *(.data .data.*)
-    _edata = .;
-  } > ram
-  _sdata = SIZEOF (.data); 
-
-  .bss 0xFF0000 + SIZEOF (.data) :
-  {
-    _start = . ;
-    *(.shbss)
-    *(.bss .bss.*)
-    *(COMMON)
-    _bend = . ;
-    end = . ;
-  } > ram
-
-  .stab 0 (NOLOAD) :
-  {
-    *(.stab)
-  }
-
-  .stabstr 0 (NOLOAD) :
-  {
-    *(.stabstr)
-  }
-
-  .eh_frame 0 (NOLOAD) :
-  {
-    *(.eh_frame)
-  } 
-}
diff --git a/sgdk/mkfiles/Makefile.rom b/sgdk/mkfiles/Makefile.rom
new file mode 100644
index 0000000..cba3a59
--- /dev/null
+++ b/sgdk/mkfiles/Makefile.rom
@@ -0,0 +1,17 @@
+#
+# Use this Makefile for most SGDK projects
+#
+
+GENDEV?=/opt/gendev
+SGDKDIR?=$(GENDEV)/sgdk
+
+# Set GDK before including default SGDK makefile
+GDK=$(SGDKDIR)
+
+include $(SGDKDIR)/mkfiles/makefile.gen
+
+# Override shell variables
+MKDIR=/bin/mkdir 
+RM=/bin/rm 
+CP=/bin/cp 
+SHELL=/bin/bash 
diff --git a/sgdk/files/Makefile.sgdk_lib b/sgdk/mkfiles/Makefile.sgdk_lib
similarity index 76%
rename from sgdk/files/Makefile.sgdk_lib
rename to sgdk/mkfiles/Makefile.sgdk_lib
index 031fec2..2745694 100644
--- a/sgdk/files/Makefile.sgdk_lib
+++ b/sgdk/mkfiles/Makefile.sgdk_lib
@@ -1,7 +1,9 @@
-GENDEV?=/opt/toolchains/gen/
+GENDEV?=/opt/gendev/
 MAKE?=make
 GENGCC_BIN=$(GENDEV)/bin
 GENBIN=$(GENDEV)/bin
+SGDKBIN=$(GENDEV)/sgdk/bin
+
 
 CC = $(GENGCC_BIN)/m68k-elf-gcc
 AR = $(GENGCC_BIN)/m68k-elf-ar
@@ -9,7 +11,7 @@ RANLIB = $(GENGCC_BIN)/m68k-elf-ranlib
 OBJC = $(GENGCC_BIN)/m68k-elf-objcopy
 RM = rm -f
 ASMZ80 = $(GENBIN)/sjasm
-BINTOS = $(GENBIN)/bintos
+BINTOS = $(SGDKBIN)/bintos
 RESCOMP= java -jar ./bin/rescomp.jar
 
 OPTION= -Dnologo_
@@ -30,13 +32,7 @@ INCS = -Iinc -Ires
 FLAGS = $(OPTION) -m68000 -Wall -O1 -c -fomit-frame-pointer $(INCS)
 FLAGSZ80 = -isrc -iinc
 
-all: appack $(libmd.a_OBJS) libmd.a
-
-appack:
-	echo -n "osBits="> tools/appack/makefile.vars
-	getconf LONG_BIT >> tools/appack/makefile.vars
-	cd tools/appack/ && make -f makefile.elf
-	cp tools/appack/appack bin/
+all: $(libmd.a_OBJS) libmd.a
 
 %.a: $(libmd.a_OBJS)
 	$(RM) $@
@@ -53,10 +49,13 @@ appack:
 	$(CC) $(FLAGS) -c $< -o $@
 
 %.o: %.s
-	$(CC) $(FLAGS) -c $< -o $@
+	$(CC) -x assembler-with-cpp -MMD $(FLAGS) -c $< -o $@
+
+%.o: %.rs
+	$(CC) -x assembler-with-cpp $(FLAGS_LIB) -c $*.rs -o $@
 
-%.s: %.res
-	$(RESCOMP) $< $@
+%.rs: %.res
+	$(RESCOMP) $*.res $*.rs -dep $*.o
 
 clean:
 	#$(RM) -f z80_drv1.c z80_drv2.c
diff --git a/sgdk/files/Makefile.xgmtool b/sgdk/mkfiles/Makefile.xgmtool
similarity index 100%
rename from sgdk/files/Makefile.xgmtool
rename to sgdk/mkfiles/Makefile.xgmtool
diff --git a/sgdk/files/makefile.vars b/sgdk/mkfiles/makefile.vars
similarity index 92%
rename from sgdk/files/makefile.vars
rename to sgdk/mkfiles/makefile.vars
index 65a3383..84ab181 100644
--- a/sgdk/files/makefile.vars
+++ b/sgdk/mkfiles/makefile.vars
@@ -3,6 +3,7 @@
 PATH := $(GENDEV)/bin:$(PATH)
 GENGCC_BIN= $(GENDEV)/bin
 GENBIN= $(GENDEV)/bin
+BIN= $(GENDEV)/bin
 
 GDK= $(GENDEV)/sgdk
 
@@ -33,7 +34,8 @@ NM = nm
 #JAVA= java
 ECHO= echo
 OBJCPY = $(GENGCC_BIN)/m68k-elf-objcopy
-ASMZ80 = $(GENBIN)/zasm
+ASMZ80 = $(GENBIN)/sjasm
+#ASMZ80 = $(GENBIN)/zasm
 #MACCER= $(BIN)/mac68k
 SIZEBND= $(GENGCC_BIN)/sizebnd
 BINTOS = $(GENBIN)/bintos
diff --git a/sgdk/files/rescomp.diff b/sgdk/patches/rescomp.diff
similarity index 100%
rename from sgdk/files/rescomp.diff
rename to sgdk/patches/rescomp.diff
diff --git a/sgdk/files/sgdk_1.34.diff b/sgdk/patches/sgdk_1.34.diff
similarity index 100%
rename from sgdk/files/sgdk_1.34.diff
rename to sgdk/patches/sgdk_1.34.diff
diff --git a/sgdk/files/sgdk_v1.40.diff b/sgdk/patches/sgdk_v1.40.diff
similarity index 100%
rename from sgdk/files/sgdk_v1.40.diff
rename to sgdk/patches/sgdk_v1.40.diff
diff --git a/sgdk/files/sgdk_v1.41.diff b/sgdk/patches/sgdk_v1.41.diff
similarity index 100%
rename from sgdk/files/sgdk_v1.41.diff
rename to sgdk/patches/sgdk_v1.41.diff
diff --git a/sgdk/files/sgdk_v1.51.diff b/sgdk/patches/sgdk_v1.51.diff
similarity index 100%
rename from sgdk/files/sgdk_v1.51.diff
rename to sgdk/patches/sgdk_v1.51.diff
diff --git a/sgdk/patches/sgdk_v1.62.diff b/sgdk/patches/sgdk_v1.62.diff
new file mode 100644
index 0000000..e69de29
diff --git a/sgdk/files/z80_drvrs.diff b/sgdk/patches/z80_drvrs.diff
similarity index 100%
rename from sgdk/files/z80_drvrs.diff
rename to sgdk/patches/z80_drvrs.diff