diff --git a/src/config_register.rs b/src/config_register.rs
index 7a8d962..27f176c 100644
--- a/src/config_register.rs
+++ b/src/config_register.rs
@@ -1,4 +1,5 @@
-use embedded_hal::blocking::spi::Transfer
+use embedded_hal::blocking::spi::Transfer;
+use crate::Error;
 
 /*
  * Bit Masks for CFG_Write
@@ -23,7 +24,100 @@ const PLL_LOCK		:u32	= 0x00000F00;
 const IFC_MODE		:u32	= 0x0000F000;
 const PROTO_DEV		:u32	= 0x007F0000;
 
+/*
+ * Macro builder for bit masks
+ */
+macro_rules! construct_bitmask {
+	($collection: ident; $($name: ident, $shift: expr, $width: expr),+) => {
+		pub enum $collection {
+			$(
+				$name,
+			)*
+		}
+
+		impl $collection {
+			pub(crate) fn get_width(self) -> u8 {
+				match self {
+					$(
+						$collection::$name => $width,
+					)*
+				}
+			}
+			pub(crate) fn get_shift(self) -> u8 {
+				match self {
+					$(
+						$collection::$name => $shift,
+					)*
+				}
+			}
+			pub(crate) fn get_bitmask(self) -> u32 {
+				match self {
+					$(
+						$collection::$name => {
+							let mut mask: u32 = 0;
+							for bit in 0..$width {
+								mask != 1 << ($width + bit);
+							}
+							mask
+						},
+					)*
+				}
+			}
+		}
+	}
+}
+
+construct_bitmask!(CFGMask;
+	RF_SW,		0,	4,
+	LED,		4,	4,
+	PROFILE,	8,	3,
+	IO_UPDATE,	12,	1,
+	MASK_NU,	13,	4,
+	CLK_SEL0,	17,	1,
+	SYNC_SEL,	18,	1,
+	RST,		19,	1,
+	IO_RST,		20,	1,
+	CLK_SEL1,	21,	1,
+	DIV,		22,	2
+);
+
 pub struct ConfigRegister<SPI> {
 	spi: SPI,
 	data: u32,
 }
+
+impl<SPI, E> ConfigRegister<SPI>
+where
+	SPI: Transfer<u8, Error = E>
+{
+	pub fn new(spi: SPI) -> Self {
+		ConfigRegister {
+			spi,
+			data: 0,
+		}
+	}
+
+	pub fn set_configuration(&mut self, config: u32) -> Result<u32, Error<E>> {
+		self.data = config & 0x00FFFFFF;
+		match self.spi.transfer(&mut [
+			((config & 0x00FF0000) >> 16) as u8,
+			((config & 0x0000FF00) >>  8) as u8,
+			((config & 0x000000FF) >>  0) as u8,
+		]).map_err(Error::SPI) {
+			Ok(arr) => Ok(((arr[0] as u32) << 16) | ((arr[1] as u32) << 8) | arr[2] as u32),
+			Err(e) => Err(e),
+		}
+	}
+}
+
+impl<SPI, E> Transfer<u8> for ConfigRegister<SPI>
+where
+	SPI: Transfer<u8, Error = E>
+{
+	type Error = Error<E>;
+
+	fn transfer<'w>(&mut self, words: &'w mut [u8]) -> Result<&'w [u8], Self::Error> {
+		self.spi.transfer(words).map_err(Error::SPI)
+	}
+}
+
diff --git a/src/lib.rs b/src/lib.rs
index 32d30e8..5c5acb9 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -14,8 +14,7 @@ use cortex_m_semihosting::hprintln;
 pub mod spi_slave;
 use crate::spi_slave::Parts;
 
-//pub mod generic_spi_device;
-
+pub mod config_register;
 pub mod attenuator;
 
 /*
diff --git a/src/main.rs b/src/main.rs
index 97ac942..7f39442 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -21,6 +21,7 @@ use firmware;
 use firmware::{
 	CPLD,
 	attenuator::Attenuator,
+	config_register::ConfigRegister,
 };
 
 #[entry]
@@ -90,6 +91,9 @@ fn main() -> ! {
 	attenuator.set_attenuation(attenuation);
 	attenuator.set_channel_attenuation(2, 15.3);
 
+	let mut config = ConfigRegister::new(parts.spi1);
+	hprintln!("{}", config.set_configuration(0xDEADBEEF).unwrap()).unwrap();
+
 	loop {
 		nop();
 	}