diff --git a/Cargo.toml b/Cargo.toml
index c3cb1c1..bd68952 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,6 +11,7 @@ edition = "2018"
 [dependencies]
 volatile-register = "0.2"
 aligned = "0.3"
+embedded-hal = "0.2"
 stm32f4xx-hal = { version = "0.8" , optional = true }
 smoltcp = { version = "0.6.0", default-features = false, features = ["proto-ipv4", "proto-ipv6", "socket-icmp", "socket-udp", "socket-tcp", "log", "verbose", "ethernet"], optional = true }
 log = "0.4"
@@ -21,13 +22,13 @@ smoltcp-phy-all = [
     "smoltcp/socket-raw", "smoltcp/socket-udp", "smoltcp/socket-tcp",
     "smoltcp/proto-ipv4", "smoltcp/proto-ipv6"
 ]
+stm32f4 = ["stm32f4xx-hal"]
 stm32f407 = ["stm32f4xx-hal/stm32f407"]
 default = []
 
 [dev-dependencies]
 cortex-m = "0.5"
 cortex-m-rt = "0.6"
-embedded-hal = "0.2"
 panic-itm = "0.4"
 
 [[example]]
diff --git a/examples/tcp_stm32f407.rs b/examples/tcp_stm32f407.rs
index 3d3896c..f9b0f1e 100644
--- a/examples/tcp_stm32f407.rs
+++ b/examples/tcp_stm32f407.rs
@@ -13,7 +13,8 @@ use stm32f4xx_hal::{
     gpio::GpioExt,
     time::U32Ext,
     stm32::{CorePeripherals, Peripherals},
-    spi::Spi
+    spi::Spi,
+    time::Hertz
 };
 use enc424j600;
 use enc424j600::EthController;
@@ -129,7 +130,7 @@ fn main() -> ! {
     let spi_eth_port = Spi::spi1(
         spi1, (spi1_sck, spi1_miso, spi1_mosi), 
         enc424j600::spi::interfaces::SPI_MODE, 
-        enc424j600::spi::interfaces::SPI_CLOCK.into(),
+        Hertz(enc424j600::spi::interfaces::SPI_CLOCK_FREQ),
         clocks);
     let mut spi_eth = enc424j600::SpiEth::new(spi_eth_port, spi1_nss);
     // Init
diff --git a/examples/tx_stm32f407.rs b/examples/tx_stm32f407.rs
index 19d07e2..df81aba 100644
--- a/examples/tx_stm32f407.rs
+++ b/examples/tx_stm32f407.rs
@@ -13,7 +13,8 @@ use stm32f4xx_hal::{
     time::U32Ext,
     stm32::{CorePeripherals, Peripherals},
     delay::Delay,
-    spi::Spi
+    spi::Spi,
+    time::Hertz
 };
 use enc424j600;
 use enc424j600::EthController;
@@ -58,7 +59,7 @@ fn main() -> ! {
     let spi_eth_port = Spi::spi1(
         spi1, (spi1_sck, spi1_miso, spi1_mosi), 
         enc424j600::spi::interfaces::SPI_MODE,
-        enc424j600::spi::interfaces::SPI_CLOCK.into(),
+        Hertz(enc424j600::spi::interfaces::SPI_CLOCK_FREQ),
         clocks);
     let mut spi_eth = enc424j600::SpiEth::new(spi_eth_port, spi1_nss);
     // Init
diff --git a/src/lib.rs b/src/lib.rs
index 2ee4573..3bed570 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,12 +1,9 @@
 #![no_std]
 
-/// STM32F4xx-HAL specific implementations
 pub mod spi;
-use stm32f4xx_hal::{
-    hal::{
-        blocking::spi::Transfer,
-        digital::v2::OutputPin,
-    }
+use embedded_hal::{
+    blocking::spi::Transfer,
+    digital::v2::OutputPin,
 };
 
 pub mod rx;
diff --git a/src/spi.rs b/src/spi.rs
index c2d8559..5489967 100644
--- a/src/spi.rs
+++ b/src/spi.rs
@@ -1,25 +1,20 @@
 use core::fmt;
-use stm32f4xx_hal::{
-    hal::{
-        blocking::spi::Transfer,
-        digital::v2::OutputPin,
-    },
+use embedded_hal::{
+    blocking::spi::Transfer,
+    digital::v2::OutputPin,
     spi,
 };
 use crate::rx;
 
 pub mod interfaces {
-    use stm32f4xx_hal::{
-        spi,
-        time::MegaHertz
-    };
+    use embedded_hal::spi;
     /// Must use SPI mode cpol=0, cpha=0
     pub const SPI_MODE: spi::Mode = spi::Mode {
         polarity: spi::Polarity::IdleLow,
         phase: spi::Phase::CaptureOnFirstTransition,
     };
     /// Max freq = 14 MHz
-    pub const SPI_CLOCK: MegaHertz = MegaHertz(14);
+    pub const SPI_CLOCK_FREQ: u32 = 14_000_000;
 }
 
 pub mod opcodes {