diff --git a/src/Kconfig b/src/Kconfig
index 16ce3531..6add97a3 100644
--- a/src/Kconfig
+++ b/src/Kconfig
@@ -13,9 +13,9 @@ choice
     prompt "Micro-controller Architecture"
     config MACH_AVR
         bool "Atmega AVR"
-    config MACH_SAM3
+    config MACH_ATSAM
         bool "SAM3/SAM4 (Due and Duet)"
-    config MACH_SAMD21
+    config MACH_ATSAMD
         bool "SAMD21 (Arduino Zero)"
     config MACH_LPC176X
         bool "LPC176x (Smoothieboard)"
@@ -30,8 +30,8 @@ choice
 endchoice
 
 source "src/avr/Kconfig"
-source "src/sam3/Kconfig"
-source "src/samd21/Kconfig"
+source "src/atsam/Kconfig"
+source "src/atsamd/Kconfig"
 source "src/lpc176x/Kconfig"
 source "src/stm32f1/Kconfig"
 source "src/pru/Kconfig"
diff --git a/src/sam3/Kconfig b/src/atsam/Kconfig
similarity index 91%
rename from src/sam3/Kconfig
rename to src/atsam/Kconfig
index c2ebb200..0ea82241 100644
--- a/src/sam3/Kconfig
+++ b/src/atsam/Kconfig
@@ -1,8 +1,8 @@
-# Kconfig settings for SAM3/SAM4 processors
+# Kconfig settings for Atmel SAM processors
 
-if MACH_SAM3
+if MACH_ATSAM
 
-config SAM3_SELECT
+config ATSAM_SELECT
     bool
     default y
     select HAVE_GPIO
@@ -13,7 +13,7 @@ config SAM3_SELECT
 
 config BOARD_DIRECTORY
     string
-    default "sam3"
+    default "atsam"
 
 choice
     prompt "Processor model"
diff --git a/src/sam3/Makefile b/src/atsam/Makefile
similarity index 82%
rename from src/sam3/Makefile
rename to src/atsam/Makefile
index a9510717..4aece952 100644
--- a/src/sam3/Makefile
+++ b/src/atsam/Makefile
@@ -1,9 +1,9 @@
-# Additional SAM3/SAM4 build rules
+# Additional ATSAM build rules
 
 # Setup the toolchain
 CROSS_PREFIX=arm-none-eabi-
 
-dirs-y += src/sam3 src/generic
+dirs-y += src/atsam src/generic
 dirs-$(CONFIG_MACH_SAM3X8E) += lib/sam3x/gcc/gcc
 dirs-$(CONFIG_MACH_SAM4S8C) += lib/sam4s/gcc/gcc
 dirs-$(CONFIG_MACH_SAM4E8E) += lib/sam4e/gcc/gcc
@@ -25,17 +25,17 @@ eflags-$(CONFIG_MACH_SAM4E8E) += -T lib/sam4e/gcc/gcc/sam4e8e_flash.ld
 CFLAGS_klipper.elf += $(eflags-y) --specs=nano.specs --specs=nosys.specs
 
 # Add source files
-src-y += sam3/main.c sam3/gpio.c sam3/i2c.c sam3/spi.c
+src-y += atsam/main.c atsam/gpio.c atsam/i2c.c atsam/spi.c
 src-y += generic/crc16_ccitt.c generic/alloc.c
 src-y += generic/armcm_irq.c generic/timer_irq.c
-src-$(CONFIG_USBSERIAL) += sam3/sam4_usb.c generic/usb_cdc.c
-src-$(CONFIG_SERIAL) += sam3/serial.c generic/serial_irq.c
-src-$(CONFIG_MACH_SAM3X8E) += sam3/adc.c sam3/timer.c
+src-$(CONFIG_USBSERIAL) += atsam/sam4_usb.c generic/usb_cdc.c
+src-$(CONFIG_SERIAL) += atsam/serial.c generic/serial_irq.c
+src-$(CONFIG_MACH_SAM3X8E) += atsam/adc.c atsam/timer.c
 src-$(CONFIG_MACH_SAM3X8E) += ../lib/sam3x/gcc/system_sam3xa.c
 src-$(CONFIG_MACH_SAM3X8E) += ../lib/sam3x/gcc/gcc/startup_sam3xa.c
-src-$(CONFIG_MACH_SAM4S8C) += sam3/adc.c sam3/sam4s_timer.c sam3/sam4s_sysinit.c
+src-$(CONFIG_MACH_SAM4S8C) += atsam/adc.c atsam/sam4s_timer.c atsam/sam4s_sysinit.c
 src-$(CONFIG_MACH_SAM4S8C) += ../lib/sam4s/gcc/gcc/startup_sam4s.c
-src-$(CONFIG_MACH_SAM4E8E) += sam3/sam4e_afec.c sam3/timer.c sam3/sam4_cache.c
+src-$(CONFIG_MACH_SAM4E8E) += atsam/sam4e_afec.c atsam/timer.c atsam/sam4_cache.c
 src-$(CONFIG_MACH_SAM4E8E) += ../lib/sam4e/gcc/system_sam4e.c
 src-$(CONFIG_MACH_SAM4E8E) += ../lib/sam4e/gcc/gcc/startup_sam4e.c
 
diff --git a/src/sam3/adc.c b/src/atsam/adc.c
similarity index 100%
rename from src/sam3/adc.c
rename to src/atsam/adc.c
diff --git a/src/sam3/gpio.c b/src/atsam/gpio.c
similarity index 100%
rename from src/sam3/gpio.c
rename to src/atsam/gpio.c
diff --git a/src/sam3/gpio.h b/src/atsam/gpio.h
similarity index 100%
rename from src/sam3/gpio.h
rename to src/atsam/gpio.h
diff --git a/src/sam3/i2c.c b/src/atsam/i2c.c
similarity index 100%
rename from src/sam3/i2c.c
rename to src/atsam/i2c.c
diff --git a/src/sam3/internal.h b/src/atsam/internal.h
similarity index 100%
rename from src/sam3/internal.h
rename to src/atsam/internal.h
diff --git a/src/sam3/main.c b/src/atsam/main.c
similarity index 100%
rename from src/sam3/main.c
rename to src/atsam/main.c
diff --git a/src/sam3/sam4_cache.c b/src/atsam/sam4_cache.c
similarity index 100%
rename from src/sam3/sam4_cache.c
rename to src/atsam/sam4_cache.c
diff --git a/src/sam3/sam4_usb.c b/src/atsam/sam4_usb.c
similarity index 100%
rename from src/sam3/sam4_usb.c
rename to src/atsam/sam4_usb.c
diff --git a/src/sam3/sam4e_afec.c b/src/atsam/sam4e_afec.c
similarity index 100%
rename from src/sam3/sam4e_afec.c
rename to src/atsam/sam4e_afec.c
diff --git a/src/sam3/sam4s_sysinit.c b/src/atsam/sam4s_sysinit.c
similarity index 100%
rename from src/sam3/sam4s_sysinit.c
rename to src/atsam/sam4s_sysinit.c
diff --git a/src/sam3/sam4s_timer.c b/src/atsam/sam4s_timer.c
similarity index 100%
rename from src/sam3/sam4s_timer.c
rename to src/atsam/sam4s_timer.c
diff --git a/src/sam3/serial.c b/src/atsam/serial.c
similarity index 100%
rename from src/sam3/serial.c
rename to src/atsam/serial.c
diff --git a/src/sam3/spi.c b/src/atsam/spi.c
similarity index 100%
rename from src/sam3/spi.c
rename to src/atsam/spi.c
diff --git a/src/sam3/timer.c b/src/atsam/timer.c
similarity index 100%
rename from src/sam3/timer.c
rename to src/atsam/timer.c
diff --git a/src/sam3/usb_cdc_ep.h b/src/atsam/usb_cdc_ep.h
similarity index 100%
rename from src/sam3/usb_cdc_ep.h
rename to src/atsam/usb_cdc_ep.h
diff --git a/src/samd21/Kconfig b/src/atsamd/Kconfig
similarity index 80%
rename from src/samd21/Kconfig
rename to src/atsamd/Kconfig
index 18bd7d81..02e21b7b 100644
--- a/src/samd21/Kconfig
+++ b/src/atsamd/Kconfig
@@ -1,8 +1,8 @@
-# Kconfig settings for SAMD21 processors
+# Kconfig settings for Atmel SAMD processors
 
-if MACH_SAMD21
+if MACH_ATSAMD
 
-config SAMD_SELECT
+config ATSAMD_SELECT
     bool
     default y
     select HAVE_GPIO
@@ -14,7 +14,13 @@ config SAMD_SELECT
 
 config BOARD_DIRECTORY
     string
-    default "samd21"
+    default "atsamd"
+
+choice
+    prompt "Processor model"
+    config MACH_SAMD21A
+        bool "SAMD21G18A (Arduino Zero)"
+endchoice
 
 config CLOCK_FREQ
     int
diff --git a/src/atsamd/Makefile b/src/atsamd/Makefile
new file mode 100644
index 00000000..ca8b2e99
--- /dev/null
+++ b/src/atsamd/Makefile
@@ -0,0 +1,54 @@
+# Additional atsamd build rules
+
+# Setup the toolchain
+CROSS_PREFIX=arm-none-eabi-
+
+dirs-y += src/atsamd src/generic
+dirs-$(CONFIG_MACH_SAMD21A) += lib/samd21/samd21a/gcc/gcc/
+
+CFLAGS-$(CONFIG_MACH_SAMD21A) += -mcpu=cortex-m0plus
+CFLAGS-$(CONFIG_MACH_SAMD21A) += -Ilib/samd21/samd21a/include -D__SAMD21G18A__
+CFLAGS += $(CFLAGS-y) -mthumb -Ilib/cmsis-core
+
+eflags-$(CONFIG_MACH_SAMD21A) += -T $(OUT)samd21a.ld
+CFLAGS_klipper.elf += $(eflags-y) --specs=nano.specs --specs=nosys.specs
+
+# Add source files
+src-y += atsamd/main.c atsamd/timer.c atsamd/clock.c atsamd/gpio.c
+src-y += generic/crc16_ccitt.c generic/alloc.c
+src-y += generic/armcm_irq.c generic/timer_irq.c
+src-$(CONFIG_USBSERIAL) += atsamd/usbserial.c generic/usb_cdc.c
+src-$(CONFIG_SERIAL) += atsamd/serial.c generic/serial_irq.c
+src-$(CONFIG_HAVE_GPIO_ADC) += atsamd/adc.c
+src-$(CONFIG_HAVE_GPIO_I2C) += atsamd/i2c.c
+src-$(CONFIG_HAVE_GPIO_SPI) += atsamd/spi.c
+src-$(CONFIG_HAVE_GPIO_HARD_PWM) += atsamd/hard_pwm.c
+src-$(CONFIG_MACH_SAMD21A) += ../lib/samd21/samd21a/gcc/gcc/startup_samd21.c
+
+# Support bootloader offset address
+target-$(CONFIG_MACH_SAMD21A) := $(OUT)samd21a.ld $(target-y)
+
+$(OUT)samd21a.ld: lib/samd21/samd21a/gcc/gcc/samd21g18a_flash.ld $(OUT)board-link
+	@echo "  Preprocessing $@"
+	$(Q)$(CPP) -P -MD -MT $@ -DFLASH_START=$(CONFIG_FLASH_START) $< -o $@
+
+# Build the additional hex and bin output files
+target-y += $(OUT)klipper.bin $(OUT)klipper.elf.hex
+
+$(OUT)klipper.bin: $(OUT)klipper.elf
+	@echo "  Creating hex file $@"
+	$(Q)$(OBJCOPY) -O binary $< $@
+
+$(OUT)klipper.elf.hex: $(OUT)klipper.elf
+	@echo "  Creating hex file $@"
+	$(Q)$(OBJCOPY) -j .text -j .relocate -O ihex $< $@
+
+# Flash rules
+lib/bossac/bin/bossac:
+	@echo "  Building bossac"
+	$(Q)make -C lib/bossac bin/bossac
+
+flash: $(OUT)klipper.bin lib/bossac/bin/bossac
+	@echo "  Flashing $^ to $(FLASH_DEVICE) via bossac"
+	$(Q)if [ -z $(FLASH_DEVICE) ]; then echo "Please specify FLASH_DEVICE"; exit 1; fi
+	$(Q)lib/bossac/bin/bossac -U -p "$(FLASH_DEVICE)" -a --offset=0x2000 -w $(OUT)klipper.bin -v -b -R
diff --git a/src/samd21/adc.c b/src/atsamd/adc.c
similarity index 100%
rename from src/samd21/adc.c
rename to src/atsamd/adc.c
diff --git a/src/samd21/clock.c b/src/atsamd/clock.c
similarity index 100%
rename from src/samd21/clock.c
rename to src/atsamd/clock.c
diff --git a/src/samd21/gpio.c b/src/atsamd/gpio.c
similarity index 100%
rename from src/samd21/gpio.c
rename to src/atsamd/gpio.c
diff --git a/src/samd21/gpio.h b/src/atsamd/gpio.h
similarity index 100%
rename from src/samd21/gpio.h
rename to src/atsamd/gpio.h
diff --git a/src/samd21/hard_pwm.c b/src/atsamd/hard_pwm.c
similarity index 100%
rename from src/samd21/hard_pwm.c
rename to src/atsamd/hard_pwm.c
diff --git a/src/samd21/i2c.c b/src/atsamd/i2c.c
similarity index 100%
rename from src/samd21/i2c.c
rename to src/atsamd/i2c.c
diff --git a/src/samd21/internal.h b/src/atsamd/internal.h
similarity index 100%
rename from src/samd21/internal.h
rename to src/atsamd/internal.h
diff --git a/src/samd21/main.c b/src/atsamd/main.c
similarity index 100%
rename from src/samd21/main.c
rename to src/atsamd/main.c
diff --git a/src/samd21/serial.c b/src/atsamd/serial.c
similarity index 100%
rename from src/samd21/serial.c
rename to src/atsamd/serial.c
diff --git a/src/samd21/spi.c b/src/atsamd/spi.c
similarity index 100%
rename from src/samd21/spi.c
rename to src/atsamd/spi.c
diff --git a/src/samd21/timer.c b/src/atsamd/timer.c
similarity index 100%
rename from src/samd21/timer.c
rename to src/atsamd/timer.c
diff --git a/src/samd21/usbserial.c b/src/atsamd/usbserial.c
similarity index 100%
rename from src/samd21/usbserial.c
rename to src/atsamd/usbserial.c
diff --git a/src/samd21/Makefile b/src/samd21/Makefile
deleted file mode 100644
index 24ef1e49..00000000
--- a/src/samd21/Makefile
+++ /dev/null
@@ -1,54 +0,0 @@
-# Additional samd21 build rules
-
-# Setup the toolchain
-CROSS_PREFIX=arm-none-eabi-
-
-dirs-y += src/samd21 src/generic
-dirs-y += lib/samd21/samd21a/gcc/gcc/
-
-CFLAGS += -mthumb -mcpu=cortex-m0plus
-CFLAGS += -Ilib/cmsis-core -Ilib/samd21/samd21a/include
-CFLAGS += -D__SAMD21G18A__
-
-CFLAGS_klipper.elf += -T $(OUT)samd21.ld
-CFLAGS_klipper.elf += --specs=nano.specs --specs=nosys.specs
-
-# Add source files
-src-y += samd21/main.c samd21/timer.c samd21/clock.c samd21/gpio.c
-src-y += generic/crc16_ccitt.c generic/alloc.c
-src-y += generic/armcm_irq.c generic/timer_irq.c
-src-y += ../lib/samd21/samd21a/gcc/gcc/startup_samd21.c
-src-$(CONFIG_USBSERIAL) += samd21/usbserial.c generic/usb_cdc.c
-src-$(CONFIG_SERIAL) += samd21/serial.c generic/serial_irq.c
-src-$(CONFIG_HAVE_GPIO_ADC) += samd21/adc.c
-src-$(CONFIG_HAVE_GPIO_I2C) += samd21/i2c.c
-src-$(CONFIG_HAVE_GPIO_SPI) += samd21/spi.c
-src-$(CONFIG_HAVE_GPIO_HARD_PWM) += samd21/hard_pwm.c
-
-# Support bootloader offset address
-target-y := $(OUT)samd21.ld $(target-y)
-
-$(OUT)samd21.ld: lib/samd21/samd21a/gcc/gcc/samd21g18a_flash.ld $(OUT)board-link
-	@echo "  Preprocessing $@"
-	$(Q)$(CPP) -P -MD -MT $@ -DFLASH_START=$(CONFIG_FLASH_START) $< -o $@
-
-# Build the additional hex and bin output files
-target-y += $(OUT)klipper.bin $(OUT)klipper.elf.hex
-
-$(OUT)klipper.bin: $(OUT)klipper.elf
-	@echo "  Creating hex file $@"
-	$(Q)$(OBJCOPY) -O binary $< $@
-
-$(OUT)klipper.elf.hex: $(OUT)klipper.elf
-	@echo "  Creating hex file $@"
-	$(Q)$(OBJCOPY) -j .text -j .relocate -O ihex $< $@
-
-# Flash rules
-lib/bossac/bin/bossac:
-	@echo "  Building bossac"
-	$(Q)make -C lib/bossac bin/bossac
-
-flash: $(OUT)klipper.bin lib/bossac/bin/bossac
-	@echo "  Flashing $^ to $(FLASH_DEVICE) via bossac"
-	$(Q)if [ -z $(FLASH_DEVICE) ]; then echo "Please specify FLASH_DEVICE"; exit 1; fi
-	$(Q)lib/bossac/bin/bossac -U -p "$(FLASH_DEVICE)" -a --offset=0x2000 -w $(OUT)klipper.bin -v -b -R
diff --git a/test/configs/sam3x8e.config b/test/configs/sam3x8e.config
index 9bf772a8..e7da6460 100644
--- a/test/configs/sam3x8e.config
+++ b/test/configs/sam3x8e.config
@@ -1,3 +1,3 @@
 # Base config file for Atmel SAM3x8e ARM processor
-CONFIG_MACH_SAM3=y
+CONFIG_MACH_ATSAM=y
 CONFIG_MACH_SAM3X8E=y
diff --git a/test/configs/sam4e8e.config b/test/configs/sam4e8e.config
index d55a5bfe..6be54c34 100644
--- a/test/configs/sam4e8e.config
+++ b/test/configs/sam4e8e.config
@@ -1,3 +1,3 @@
 # Base config file for Atmel SAM4E8E ARM processor
-CONFIG_MACH_SAM3=y
+CONFIG_MACH_ATSAM=y
 CONFIG_MACH_SAM4E8E=y
diff --git a/test/configs/sam4s8c.config b/test/configs/sam4s8c.config
index 3b032bea..20c539fc 100644
--- a/test/configs/sam4s8c.config
+++ b/test/configs/sam4s8c.config
@@ -1,3 +1,3 @@
 # Base config file for Atmel SAM4S8C ARM processor
-CONFIG_MACH_SAM3=y
+CONFIG_MACH_ATSAM=y
 CONFIG_MACH_SAM4S8C=y
diff --git a/test/configs/samd21.config b/test/configs/samd21.config
index f40da125..8dd361d1 100644
--- a/test/configs/samd21.config
+++ b/test/configs/samd21.config
@@ -1,2 +1,3 @@
 # Base config file for SAMD21 boards
+CONFIG_MACH_ATSAMD=y
 CONFIG_MACH_SAMD21=y