diff --git a/CHANGELOG.md b/CHANGELOG.md
index 30a8a1a5..5bbf0330 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## 0.15.0 (TBD)
+
+* **Gpio**: (Breaking change) Rename `PullUpDown` enum to `Bias`, and `set_pullupdown` to `set_bias`.
+* **Gpio**: (Breaking change) Add support for new modes `Alt6`, `Alt7` and `Alt8`.
+
 ## 0.14.1 (November 25, 2022)
 
 * **Gpio**: Fix subtract underflow panic in software-based PWM.
diff --git a/src/gpio.rs b/src/gpio.rs
index 15a0abaf..eea2d942 100644
--- a/src/gpio.rs
+++ b/src/gpio.rs
@@ -298,18 +298,18 @@ impl Not for Level {
 
 /// Built-in pull-up/pull-down resistor states.
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
-pub enum PullUpDown {
+pub enum Bias {
     Off = 0b00,
     PullDown = 0b01,
     PullUp = 0b10,
 }
 
-impl fmt::Display for PullUpDown {
+impl fmt::Display for Bias {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match *self {
-            PullUpDown::Off => write!(f, "Off"),
-            PullUpDown::PullDown => write!(f, "PullDown"),
-            PullUpDown::PullUp => write!(f, "PullUp"),
+            Bias::Off => write!(f, "Off"),
+            Bias::PullDown => write!(f, "PullDown"),
+            Bias::PullUp => write!(f, "PullUp"),
         }
     }
 }
diff --git a/src/gpio/gpiomem.rs b/src/gpio/gpiomem.rs
index f6ba78b6..189a7be2 100644
--- a/src/gpio/gpiomem.rs
+++ b/src/gpio/gpiomem.rs
@@ -1,4 +1,4 @@
-use crate::gpio::{Level, Mode, PullUpDown};
+use crate::gpio::{Bias, Level, Mode};
 
 pub mod bcm;
 pub mod rp1;
@@ -9,5 +9,5 @@ pub(crate) trait GpioRegisters: std::fmt::Debug + Sync + Send {
     fn level(&self, pin: u8) -> Level;
     fn mode(&self, pin: u8) -> Mode;
     fn set_mode(&self, pin: u8, mode: Mode);
-    fn set_pullupdown(&self, pin: u8, pud: PullUpDown);
+    fn set_bias(&self, pin: u8, bias: Bias);
 }
diff --git a/src/gpio/gpiomem/bcm.rs b/src/gpio/gpiomem/bcm.rs
index 2b684147..63f9cebb 100644
--- a/src/gpio/gpiomem/bcm.rs
+++ b/src/gpio/gpiomem/bcm.rs
@@ -11,7 +11,7 @@ use std::time::Duration;
 use libc::{self, c_void, off_t, size_t, MAP_FAILED, MAP_SHARED, O_SYNC, PROT_READ, PROT_WRITE};
 
 use crate::gpio::gpiomem::GpioRegisters;
-use crate::gpio::{Error, Level, Mode, PullUpDown, Result};
+use crate::gpio::{Bias, Error, Level, Mode, Result};
 use crate::system::{DeviceInfo, SoC};
 
 const PATH_DEV_GPIOMEM: &str = "/dev/gpiomem";
@@ -248,7 +248,7 @@ impl GpioRegisters for GpioMem {
         self.locks[offset].store(false, Ordering::SeqCst);
     }
 
-    fn set_pullupdown(&self, pin: u8, pud: PullUpDown) {
+    fn set_bias(&self, pin: u8, bias: Bias) {
         // Offset for register.
         let offset: usize;
         // Bit shift for pin position within register value.
@@ -263,10 +263,10 @@ impl GpioRegisters for GpioMem {
             let lock = GPPUD_CNTRL_REG0 + pin as usize / 32;
 
             // Pull up vs pull down has a reverse bit pattern on BCM2711 vs others.
-            let pud = match pud {
-                PullUpDown::Off => 0b00u32,
-                PullUpDown::PullDown => 0b10,
-                PullUpDown::PullUp => 0b01,
+            let pud = match bias {
+                Bias::Off => 0b00u32,
+                Bias::PullDown => 0b10,
+                Bias::PullUp => 0b01,
             };
 
             loop {
@@ -304,7 +304,7 @@ impl GpioRegisters for GpioMem {
 
             // Set the control signal in GPPUD.
             let reg_value = self.read(GPPUD);
-            self.write(GPPUD, (reg_value & !0b11) | ((pud as u32) & 0b11));
+            self.write(GPPUD, (reg_value & !0b11) | ((bias as u32) & 0b11));
 
             // The datasheet mentions waiting at least 150 cycles for set-up and hold, but
             // doesn't state which clock is used. This is likely the VPU clock (see
diff --git a/src/gpio/gpiomem/rp1.rs b/src/gpio/gpiomem/rp1.rs
index 511162fc..6dafe6f3 100644
--- a/src/gpio/gpiomem/rp1.rs
+++ b/src/gpio/gpiomem/rp1.rs
@@ -7,7 +7,7 @@ use std::ptr;
 
 use libc::{self, c_void, size_t, MAP_FAILED, MAP_SHARED, O_SYNC, PROT_READ, PROT_WRITE};
 
-use crate::gpio::{Error, Level, Mode, PullUpDown, Result};
+use crate::gpio::{Bias, Error, Level, Mode, Result};
 use crate::system::{DeviceInfo, SoC};
 
 use super::GpioRegisters;
@@ -151,7 +151,7 @@ impl GpioRegisters for GpioMem {
         unimplemented!()
     }
 
-    fn set_pullupdown(&self, pin: u8, pud: PullUpDown) {
+    fn set_bias(&self, pin: u8, bias: Bias) {
         unimplemented!()
     }
 }
diff --git a/src/gpio/pin.rs b/src/gpio/pin.rs
index 2c5abc29..ee5820ca 100644
--- a/src/gpio/pin.rs
+++ b/src/gpio/pin.rs
@@ -4,7 +4,7 @@ use std::sync::Arc;
 use std::time::Duration;
 
 use super::soft_pwm::SoftPwm;
-use crate::gpio::{interrupt::AsyncInterrupt, GpioState, Level, Mode, PullUpDown, Result, Trigger};
+use crate::gpio::{interrupt::AsyncInterrupt, Bias, GpioState, Level, Mode, Result, Trigger};
 
 const NANOS_PER_SEC: f64 = 1_000_000_000.0;
 
@@ -207,8 +207,8 @@ macro_rules! impl_drop {
                     self.pin.set_mode(prev_mode);
                 }
 
-                if self.pud_mode != PullUpDown::Off {
-                    self.pin.set_pullupdown(PullUpDown::Off);
+                if self.bias != Bias::Off {
+                    self.pin.set_bias(Bias::Off);
                 }
             }
         }
@@ -296,7 +296,7 @@ impl Pin {
     /// [`Input`]: enum.Mode.html#variant.Input
     #[inline]
     pub fn into_input(self) -> InputPin {
-        InputPin::new(self, PullUpDown::Off)
+        InputPin::new(self, Bias::Off)
     }
 
     /// Consumes the `Pin` and returns an [`InputPin`]. Sets the mode to [`Input`]
@@ -310,7 +310,7 @@ impl Pin {
     /// [`reset_on_drop`]: struct.InputPin.html#method.set_reset_on_drop
     #[inline]
     pub fn into_input_pulldown(self) -> InputPin {
-        InputPin::new(self, PullUpDown::PullDown)
+        InputPin::new(self, Bias::PullDown)
     }
 
     /// Consumes the `Pin` and returns an [`InputPin`]. Sets the mode to [`Input`]
@@ -324,7 +324,7 @@ impl Pin {
     /// [`reset_on_drop`]: struct.InputPin.html#method.set_reset_on_drop
     #[inline]
     pub fn into_input_pullup(self) -> InputPin {
-        InputPin::new(self, PullUpDown::PullUp)
+        InputPin::new(self, Bias::PullUp)
     }
 
     /// Consumes the `Pin` and returns an [`OutputPin`]. Sets the mode to [`Mode::Output`]
@@ -367,8 +367,8 @@ impl Pin {
     }
 
     #[inline]
-    pub(crate) fn set_pullupdown(&mut self, pud: PullUpDown) {
-        self.gpio_state.gpio_mem.set_pullupdown(self.pin, pud);
+    pub(crate) fn set_bias(&mut self, bias: Bias) {
+        self.gpio_state.gpio_mem.set_bias(self.pin, bias);
     }
 
     #[inline]
@@ -424,11 +424,11 @@ pub struct InputPin {
     prev_mode: Option<Mode>,
     async_interrupt: Option<AsyncInterrupt>,
     reset_on_drop: bool,
-    pud_mode: PullUpDown,
+    bias: Bias,
 }
 
 impl InputPin {
-    pub(crate) fn new(mut pin: Pin, pud_mode: PullUpDown) -> InputPin {
+    pub(crate) fn new(mut pin: Pin, bias: Bias) -> InputPin {
         let prev_mode = pin.mode();
 
         let prev_mode = if prev_mode == Mode::Input {
@@ -438,14 +438,14 @@ impl InputPin {
             Some(prev_mode)
         };
 
-        pin.set_pullupdown(pud_mode);
+        pin.set_bias(bias);
 
         InputPin {
             pin,
             prev_mode,
             async_interrupt: None,
             reset_on_drop: true,
-            pud_mode,
+            bias,
         }
     }
 
@@ -578,7 +578,7 @@ pub struct OutputPin {
     pin: Pin,
     prev_mode: Option<Mode>,
     reset_on_drop: bool,
-    pud_mode: PullUpDown,
+    bias: Bias,
     pub(crate) soft_pwm: Option<SoftPwm>,
     // Stores the softpwm frequency. Used for embedded_hal::PwmPin.
     #[cfg(feature = "hal")]
@@ -603,7 +603,7 @@ impl OutputPin {
             pin,
             prev_mode,
             reset_on_drop: true,
-            pud_mode: PullUpDown::Off,
+            bias: Bias::Off,
             soft_pwm: None,
             #[cfg(feature = "hal")]
             frequency: 0.0,
@@ -671,7 +671,7 @@ pub struct IoPin {
     mode: Mode,
     prev_mode: Option<Mode>,
     reset_on_drop: bool,
-    pud_mode: PullUpDown,
+    bias: Bias,
     pub(crate) soft_pwm: Option<SoftPwm>,
     // Stores the softpwm frequency. Used for embedded_hal::PwmPin.
     #[cfg(feature = "hal")]
@@ -697,7 +697,7 @@ impl IoPin {
             mode,
             prev_mode,
             reset_on_drop: true,
-            pud_mode: PullUpDown::Off,
+            bias: Bias::Off,
             soft_pwm: None,
             #[cfg(feature = "hal")]
             frequency: 0.0,
@@ -730,9 +730,9 @@ impl IoPin {
 
     /// Configures the built-in pull-up/pull-down resistors.
     #[inline]
-    pub fn set_pullupdown(&mut self, pud: PullUpDown) {
-        self.pin.set_pullupdown(pud);
-        self.pud_mode = pud;
+    pub fn set_bias(&mut self, bias: Bias) {
+        self.pin.set_bias(bias);
+        self.bias = bias;
     }
 
     impl_input!();