diff --git a/README.md b/README.md
index ff5d736..74104b0 100644
--- a/README.md
+++ b/README.md
@@ -61,7 +61,8 @@ Programming the STM32
 ```
 cd board
 ./get_sdk.sh
-make
+make recover   # initially
+make           # future
 ```
 
 Programming the ESP
diff --git a/board/build.mk b/board/build.mk
index f29e897..a2d3017 100644
--- a/board/build.mk
+++ b/board/build.mk
@@ -27,6 +27,7 @@ bin: obj/$(PROJ_NAME).bin
 # this flashes everything
 recover: obj/bootstub.$(PROJ_NAME).bin obj/$(PROJ_NAME).bin
 	-python -c "from panda import Panda; Panda().reset(enter_bootloader=True)"
+	sleep 0.5
 	$(DFU_UTIL) -a 0 -s 0x08004000 -D obj/$(PROJ_NAME).bin
 	$(DFU_UTIL) -a 0 -s 0x08000000:leave -D obj/bootstub.$(PROJ_NAME).bin
 
@@ -46,7 +47,7 @@ endif
 obj/cert.h: ../crypto/getcertheader.py
 	../crypto/getcertheader.py ../certs/debug.pub ../certs/release.pub > $@
 
-obj/%.$(PROJ_NAME).o: %.c obj/cert.h obj/gitversion.h config.h
+obj/%.$(PROJ_NAME).o: %.c obj/cert.h obj/gitversion.h config.h drivers/*.h
 	$(CC) $(CFLAGS) -o $@ -c $<
 
 obj/%.$(PROJ_NAME).o: ../crypto/%.c
diff --git a/board/dac.h b/board/drivers/dac.h
similarity index 100%
rename from board/dac.h
rename to board/drivers/dac.h
diff --git a/board/drivers/drivers.h b/board/drivers/drivers.h
index 1f48e7f..732746d 100644
--- a/board/drivers/drivers.h
+++ b/board/drivers/drivers.h
@@ -1,3 +1,6 @@
+#ifndef PANDA_DRIVERS_H
+#define PANDA_DRIVERS_H
+
 // ********************* USB *********************
 // IRQs: OTG_FS
 
@@ -61,6 +64,12 @@ void adc_init();
 uint32_t adc_get(int channel);
 
 
+// ********************* DAC *********************
+
+void dac_init();
+uint32_t dac_set(int channel, uint32_t value);
+
+
 // ********************* TIMER *********************
 
 void timer_init(TIM_TypeDef *TIM, int psc);
@@ -107,4 +116,5 @@ void can_init_all();
 void can_send(CAN_FIFOMailBox_TypeDef *to_push, uint8_t bus_number);
 int can_pop(can_ring *q, CAN_FIFOMailBox_TypeDef *elem);
 
+#endif
 
diff --git a/boardesp/.gitignore b/boardesp/.gitignore
index ddbccd3..bff8f3b 100644
--- a/boardesp/.gitignore
+++ b/boardesp/.gitignore
@@ -4,3 +4,4 @@ esp-open-sdk
 a.out
 cert.h
 gitversion.h
+esp-open-sdk.dmg
diff --git a/boardesp/get_sdk_mac.sh b/boardesp/get_sdk_mac.sh
new file mode 100755
index 0000000..0bf3dda
--- /dev/null
+++ b/boardesp/get_sdk_mac.sh
@@ -0,0 +1,28 @@
+#!/bin/bash
+brew install gnu-sed --with-default-names
+brew tap homebrew/dupes
+brew install gperf
+brew install grep
+brew install autoconf
+brew install binutils
+brew install gawk
+brew install wget
+brew install automake
+brew install libtool
+brew install help2man
+
+hdiutil create esp-open-sdk.dmg -volname "esp-open-sdk" -size 1g -fs "Case-sensitive HFS+"
+hdiutil mount esp-open-sdk.dmg
+ln -s /Volumes/esp-open-sdk esp-open-sdk
+mkdir -p esp-open-sdk
+cd esp-open-sdk
+
+git init
+git remote add origin https://github.com/pfalcon/esp-open-sdk.git
+git fetch origin
+git checkout 03f5e898a059451ec5f3de30e7feff30455f7cec
+git submodule init
+git submodule update --recursive
+
+make STANDALONE=y
+