diff --git a/Cargo.lock b/Cargo.lock
index 3bf1cf0cfd..98a76081ae 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -856,6 +856,18 @@ dependencies = [
  "stm32f4",
 ]
 
+[[package]]
+name = "demo-stm32f4-nucleo"
+version = "0.1.0"
+dependencies = [
+ "build-util",
+ "cfg-if",
+ "cortex-m",
+ "cortex-m-rt",
+ "kern",
+ "stm32f4",
+]
+
 [[package]]
 name = "demo-stm32g0-nucleo"
 version = "0.1.0"
@@ -2245,6 +2257,7 @@ version = "0.1.0"
 dependencies = [
  "cfg-if",
  "num-traits",
+ "stm32f4",
  "stm32g0",
  "stm32h7",
  "userlib",
@@ -2306,6 +2319,7 @@ dependencies = [
  "idol",
  "idol-runtime",
  "num-traits",
+ "stm32f4",
  "stm32g0",
  "stm32h7",
  "task-jefe-api",
@@ -2419,7 +2433,6 @@ dependencies = [
  "lpc55-pac",
  "num-traits",
  "stm32f3",
- "stm32f4",
  "task-config",
  "userlib",
  "zerocopy 0.6.6",
@@ -4662,11 +4675,11 @@ dependencies = [
 
 [[package]]
 name = "stm32f4"
-version = "0.13.0"
+version = "0.15.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da3d56009c8f32e4f208dbea17df72484154d1040a8969b75d8c73eb7b18fe8f"
+checksum = "fb94729242cd1aebe6dab42a2ca0131985ae93bc3ab2751b680df724bb35528d"
 dependencies = [
- "bare-metal 0.2.5",
+ "bare-metal 1.0.0",
  "cortex-m",
  "cortex-m-rt",
  "vcell",
diff --git a/Cargo.toml b/Cargo.toml
index 1c376057b9..4a01f6474c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -107,7 +107,7 @@ spin = { version = "0.9.4", default-features = false, features = ["mutex", "spin
 ssmarshal = { version = "1.0.0", default-features = false }
 static_assertions = { version = "1", default-features = false }
 stm32f3 = { version = "0.13.0", default-features = false }
-stm32f4 = { version = "0.13.0", default-features = false }
+stm32f4 = { version = "0.15.1", default-features = false }
 stm32h7 = { version = "0.14", default-features = false }
 stm32g0 = { version = "0.15.1", default-features = false }
 strsim = { version = "0.10.0", default-features = false }
diff --git a/app/demo-stm32f4-discovery/app.toml b/app/demo-stm32f4-discovery/app.toml
index 5161437106..bd6c621e00 100644
--- a/app/demo-stm32f4-discovery/app.toml
+++ b/app/demo-stm32f4-discovery/app.toml
@@ -17,9 +17,19 @@ start = true
 stacksize = 1536
 notifications = ["fault", "timer"]
 
+[tasks.sys]
+name = "drv-stm32xx-sys"
+priority = 1
+max-sizes = {flash = 2048, ram = 256}
+uses = ["rcc", "gpio"]
+start = true
+features = ["f407", "no-ipc-counters"]
+stacksize = 256
+task-slots = ["jefe"]
+
 [tasks.rcc_driver]
 name = "drv-stm32fx-rcc"
-features = ["f4"]
+features = ["f407"]
 priority = 1
 max-sizes = {flash = 8192, ram = 1024}
 uses = ["rcc"]
@@ -27,10 +37,10 @@ start = true
 
 [tasks.usart_driver]
 name = "drv-stm32fx-usart"
-features = ["stm32f4"]
+features = ["f407"]
 priority = 2
 max-sizes = {flash = 8192, ram = 1024}
-uses = ["usart2", "gpioa"]
+uses = ["usart2", "gpio"]
 start = true
 notifications = ["usart-irq"]
 interrupts = {"usart2.irq" = "usart-irq"}
@@ -41,9 +51,8 @@ name = "drv-user-leds"
 features = ["stm32f4"]
 priority = 2
 max-sizes = {flash = 8192, ram = 1024}
-uses = ["gpiod"]
 start = true
-task-slots = ["rcc_driver"]
+task-slots = ["rcc_driver", "sys"]
 notifications = ["timer"]
 
 [tasks.ping]
diff --git a/app/demo-stm32f4-nucleo/Cargo.toml b/app/demo-stm32f4-nucleo/Cargo.toml
new file mode 100644
index 0000000000..4dd7693a56
--- /dev/null
+++ b/app/demo-stm32f4-nucleo/Cargo.toml
@@ -0,0 +1,30 @@
+[package]
+edition = "2021"
+readme = "README.md"
+name = "demo-stm32f4-nucleo"
+version = "0.1.0"
+
+[features]
+f429 = ["stm32f4/stm32f429", "kern/nano"]
+dump = ["kern/dump"]
+
+[dependencies]
+cortex-m = { workspace = true }
+cortex-m-rt = { workspace = true }
+cfg-if = { workspace = true }
+stm32f4 = { workspace = true, features = ["stm32f429", "rt"] }
+
+kern = { path = "../../sys/kern" }
+
+[build-dependencies]
+build-util = {path = "../../build/util"}
+
+# this lets you use `cargo fix`!
+[[bin]]
+name = "demo-stm32f4-nucleo"
+test = false
+doctest = false
+bench = false
+
+[lints]
+workspace = true
diff --git a/app/demo-stm32f4-nucleo/README.md b/app/demo-stm32f4-nucleo/README.md
new file mode 100644
index 0000000000..984cf2cd23
--- /dev/null
+++ b/app/demo-stm32f4-nucleo/README.md
@@ -0,0 +1 @@
+# STM32F4 demo application for the NUCLEO-F429ZI board
diff --git a/app/demo-stm32f4-nucleo/app.toml b/app/demo-stm32f4-nucleo/app.toml
new file mode 100644
index 0000000000..6160af78b6
--- /dev/null
+++ b/app/demo-stm32f4-nucleo/app.toml
@@ -0,0 +1,86 @@
+name = "demo-stm32f4-nucleo"
+target = "thumbv7em-none-eabihf"
+board = "stm32f429-nucleo"
+chip = "../../chips/stm32f4"
+stacksize = 896
+
+[kernel]
+name = "demo-stm32f4-nucleo"
+requires = {flash = 20000, ram = 3072}
+
+[tasks.jefe]
+name = "task-jefe"
+priority = 0
+max-sizes = {flash = 8192, ram = 2048}
+start = true
+stacksize = 1536
+notifications = ["fault", "timer"]
+
+[tasks.sys]
+name = "drv-stm32xx-sys"
+priority = 1
+max-sizes = {flash = 2048, ram = 256}
+uses = ["rcc", "gpio"]
+start = true
+features = ["f429", "no-ipc-counters"]
+stacksize = 256
+task-slots = ["jefe"]
+
+[tasks.rcc_driver]
+name = "drv-stm32fx-rcc"
+features = ["f429"]
+priority = 1
+max-sizes = {flash = 8192, ram = 1024}
+uses = ["rcc"]
+start = true
+
+[tasks.usart_driver]
+name = "drv-stm32fx-usart"
+features = ["f429"]
+priority = 2
+max-sizes = {flash = 8192, ram = 1024}
+uses = ["usart2", "gpio"]
+start = true
+notifications = ["usart-irq"]
+interrupts = {"usart2.irq" = "usart-irq"}
+task-slots = ["rcc_driver"]
+
+[tasks.user_leds]
+name = "drv-user-leds"
+features = ["stm32f4"]
+priority = 2
+max-sizes = {flash = 8192, ram = 1024}
+start = true
+task-slots = ["rcc_driver", "sys"]
+notifications = ["timer"]
+
+[tasks.ping]
+name = "task-ping"
+features = ["uart"]
+priority = 4
+max-sizes = {flash = 8192, ram = 1024}
+stacksize = 512
+start = true
+task-slots = [{peer = "pong"}, "usart_driver"]
+
+[tasks.pong]
+name = "task-pong"
+priority = 3
+max-sizes = {flash = 8192, ram = 1024}
+start = true
+task-slots = ["user_leds"]
+notifications = ["timer"]
+
+[tasks.hiffy]
+name = "task-hiffy"
+priority = 3
+max-sizes = {flash = 16384, ram = 16384 }
+stacksize = 2048
+start = true
+
+[tasks.idle]
+name = "task-idle"
+priority = 5
+max-sizes = {flash = 128, ram = 256}
+stacksize = 256
+start = true
diff --git a/app/demo-stm32f4-nucleo/build.rs b/app/demo-stm32f4-nucleo/build.rs
new file mode 100644
index 0000000000..2800895934
--- /dev/null
+++ b/app/demo-stm32f4-nucleo/build.rs
@@ -0,0 +1,7 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+fn main() {
+    build_util::expose_target_board();
+}
diff --git a/app/demo-stm32f4-nucleo/src/main.rs b/app/demo-stm32f4-nucleo/src/main.rs
new file mode 100644
index 0000000000..4c5502eabf
--- /dev/null
+++ b/app/demo-stm32f4-nucleo/src/main.rs
@@ -0,0 +1,19 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+#![no_std]
+#![no_main]
+
+// We have to do this if we don't otherwise use it to ensure its vector table
+// gets linked in.
+extern crate stm32f4;
+
+use cortex_m_rt::entry;
+
+#[entry]
+fn main() -> ! {
+    const CYCLES_PER_MS: u32 = 16_000;
+
+    unsafe { kern::startup::start_kernel(CYCLES_PER_MS) }
+}
diff --git a/boards/stm32f429-nucleo.toml b/boards/stm32f429-nucleo.toml
new file mode 100644
index 0000000000..56b2669e83
--- /dev/null
+++ b/boards/stm32f429-nucleo.toml
@@ -0,0 +1,2 @@
+[probe-rs]
+chip-name = "STM32F429ZITx"
diff --git a/chips/stm32f4/chip.toml b/chips/stm32f4/chip.toml
index 2d8a8b403f..519bdcc26e 100644
--- a/chips/stm32f4/chip.toml
+++ b/chips/stm32f4/chip.toml
@@ -7,10 +7,6 @@ interrupts = { irq = 38 }
 address = 0x40023800
 size = 1024
 
-[gpioa]
+[gpio]
 address = 0x40020000
-size = 1024
-
-[gpiod]
-address = 0x40020c00
-size = 1024
+size = 16384
diff --git a/drv/stm32fx-rcc/Cargo.toml b/drv/stm32fx-rcc/Cargo.toml
index 2c284c1d7a..af78c85826 100644
--- a/drv/stm32fx-rcc/Cargo.toml
+++ b/drv/stm32fx-rcc/Cargo.toml
@@ -13,7 +13,8 @@ userlib = { path = "../../sys/userlib", features = ["panic-messages"] }
 
 [features]
 f3 = ["stm32f3/stm32f303"]
-f4 = ["stm32f4/stm32f407"]
+f407 = ["stm32f4/stm32f407"]
+f429 = ["stm32f4/stm32f429"]
 
 # This section is here to discourage RLS/rust-analyzer from doing test builds,
 # since test builds don't work for cross compilation.
diff --git a/drv/stm32fx-rcc/src/main.rs b/drv/stm32fx-rcc/src/main.rs
index 2f04977876..013e1a8e3a 100644
--- a/drv/stm32fx-rcc/src/main.rs
+++ b/drv/stm32fx-rcc/src/main.rs
@@ -53,9 +53,12 @@
 #[cfg(feature = "stm32f3")]
 use stm32f3::stm32f303 as device;
 
-#[cfg(feature = "stm32f4")]
+#[cfg(feature = "f407")]
 use stm32f4::stm32f407 as device;
 
+#[cfg(feature = "f429")]
+use stm32f4::stm32f429 as device;
+
 use userlib::*;
 use zerocopy::AsBytes;
 
diff --git a/drv/stm32fx-usart/Cargo.toml b/drv/stm32fx-usart/Cargo.toml
index efddc78234..f397cae19d 100644
--- a/drv/stm32fx-usart/Cargo.toml
+++ b/drv/stm32fx-usart/Cargo.toml
@@ -6,11 +6,15 @@ edition = "2021"
 [dependencies]
 num-traits = { workspace = true }
 stm32f3 = { workspace = true, optional = true, features = ["stm32f303"] }
-stm32f4 = { workspace = true, optional = true, features = ["stm32f407"] }
+stm32f4 = { workspace = true, optional = true }
 zerocopy = { workspace = true }
 
 userlib = { path = "../../sys/userlib", features = ["panic-messages"] }
 
+[features]
+f407 = [ "stm32f4/stm32f407" ]
+f429 = [ "stm32f4/stm32f429" ]
+
 [build-dependencies]
 build-util = { path = "../../build/util" }
 
diff --git a/drv/stm32fx-usart/src/main.rs b/drv/stm32fx-usart/src/main.rs
index d0e8019008..2062f3d73c 100644
--- a/drv/stm32fx-usart/src/main.rs
+++ b/drv/stm32fx-usart/src/main.rs
@@ -13,7 +13,10 @@
 #![no_std]
 #![no_main]
 
-#[cfg(feature = "stm32f4")]
+#[cfg(feature = "f429")]
+use stm32f4::stm32f429 as device;
+
+#[cfg(feature = "f407")]
 use stm32f4::stm32f407 as device;
 
 #[cfg(feature = "stm32f3")]
@@ -74,7 +77,7 @@ fn main() -> ! {
             .write(|w| w.brr().bits((CLOCK_HZ / BAUDRATE) as u16));
     }
 
-    #[cfg(feature = "stm32f4")]
+    #[cfg(any(feature = "f407", feature = "f429"))]
     {
         const CLOCK_HZ: u32 = 16_000_000;
         const CYCLES_PER_BIT: u32 = (CLOCK_HZ + (BAUDRATE / 2)) / BAUDRATE;
@@ -126,7 +129,7 @@ fn main() -> ! {
 
                     #[cfg(feature = "stm32f3")]
                     let txe = usart.isr.read().txe().bit();
-                    #[cfg(feature = "stm32f4")]
+                    #[cfg(any(feature = "f407", feature = "f429"))]
                     let txe = usart.sr.read().txe().bit();
                     if txe {
                         // TX register empty. Do we need to send something?
@@ -208,7 +211,7 @@ fn turn_on_gpioa() {
 
     #[cfg(feature = "stm32f3")]
     let pnum = 17; // see bits in AHBENR
-    #[cfg(feature = "stm32f4")]
+    #[cfg(any(feature = "f407", feature = "f429"))]
     let pnum = 0; // see bits in AHB1ENR
 
     let (code, _) = userlib::sys_send(
@@ -250,7 +253,7 @@ fn step_transmit(
         // Stuff byte into transmitter.
         #[cfg(feature = "stm32f3")]
         usart.tdr.write(|w| w.tdr().bits(u16::from(byte)));
-        #[cfg(feature = "stm32f4")]
+        #[cfg(any(feature = "f407", feature = "f429"))]
         usart.dr.write(|w| w.dr().bits(u16::from(byte)));
 
         txs.pos += 1;
diff --git a/drv/stm32xx-gpio-common/Cargo.toml b/drv/stm32xx-gpio-common/Cargo.toml
index 4a2ebec37a..4a2690ebf4 100644
--- a/drv/stm32xx-gpio-common/Cargo.toml
+++ b/drv/stm32xx-gpio-common/Cargo.toml
@@ -8,6 +8,7 @@ cfg-if = { workspace = true }
 num-traits = { workspace = true }
 stm32g0 = { workspace = true, optional = true }
 stm32h7 = { workspace = true, optional = true }
+stm32f4 = { workspace = true, optional = true }
 zerocopy = { workspace = true }
 
 userlib = { path = "../../sys/userlib" }
@@ -57,12 +58,29 @@ family-stm32h7 = [
 model-stm32h743 = ["family-stm32h7"]
 model-stm32h753 = ["family-stm32h7"]
 
+family-stm32f4 = [
+    "stm32f4",
+    "has-gpioa-type",
+    "has-gpiob-type",
+    "has-gpiok-type",
+    "has-port-gpioe",
+    "has-port-gpiof",
+    "has-port-gpiog",
+    "has-port-gpioh",
+    "has-port-gpioi",
+    "has-port-gpioj",
+    "has-port-gpiok",
+]
+model-stm32f407 = ["family-stm32f4"]
+model-stm32f429 = ["family-stm32f4"]
+
 # The has-gpioX-type features indicates that the PAC for the chosen model calls
 # at least some of the GPIO ports `gpioX`. Note that this has nothing to do
 # with the actual identity of the port; GPIOX is probably called `gpioX` but
 # GPIOZ might be too.
 has-gpioa-type = []
 has-gpiob-type = []
+has-gpiok-type = []
 
 # The has-port-gpioX features indicate that the model or family includes the
 # given GPIO port in the memory map. Numbering here starts at E because it is a
diff --git a/drv/stm32xx-gpio-common/src/server.rs b/drv/stm32xx-gpio-common/src/server.rs
index 517594859f..f1fb5e4a01 100644
--- a/drv/stm32xx-gpio-common/src/server.rs
+++ b/drv/stm32xx-gpio-common/src/server.rs
@@ -38,6 +38,17 @@ cfg_if::cfg_if! {
                 compile_error!("unsupported or missing SoC model feature");
             }
         }
+    } else if #[cfg(feature = "family-stm32f4")] {
+        use stm32f4 as pac;
+        cfg_if::cfg_if! {
+            if #[cfg(feature = "model-stm32f407")] {
+                use pac::stm32f407 as device;
+            } else if #[cfg(feature = "model-stm32f429")] {
+                use pac::stm32f429 as device;
+            } else {
+                compile_error!("unsupported or missing SoC model feature");
+            }
+        }
     } else {
         compile_error!("unsupported or missing SoC family feature");
     }
@@ -259,6 +270,10 @@ impl_gpio_periph!(gpioa);
 #[cfg(feature = "has-gpiob-type")]
 impl_gpio_periph!(gpiob);
 
+// At least F4 distinguishes gpiok from other ports.
+#[cfg(feature = "has-gpiok-type")]
+impl_gpio_periph!(gpiok);
+
 // Add add'l types here as PAC crates invent more - L4 in particular
 // distinguishes gpioc, so if we support that family, gpioc would go here.
 
diff --git a/drv/stm32xx-sys-api/Cargo.toml b/drv/stm32xx-sys-api/Cargo.toml
index b7bc0e2655..115e145b6e 100644
--- a/drv/stm32xx-sys-api/Cargo.toml
+++ b/drv/stm32xx-sys-api/Cargo.toml
@@ -30,6 +30,10 @@ g031 = ["family-stm32g0", "drv-stm32xx-gpio-common/model-stm32g031"]
 g070 = ["family-stm32g0", "drv-stm32xx-gpio-common/model-stm32g070"]
 g0b1 = ["family-stm32g0", "drv-stm32xx-gpio-common/model-stm32g0b1"]
 
+family-stm32f4 = ["drv-stm32xx-gpio-common/family-stm32f4"]
+f407 = ["family-stm32f4", "drv-stm32xx-gpio-common/model-stm32f407"]
+f429 = ["family-stm32f4", "drv-stm32xx-gpio-common/model-stm32f429"]
+
 # This section is here to discourage RLS/rust-analyzer from doing test builds,
 # since test builds don't work for cross compilation.
 [lib]
diff --git a/drv/stm32xx-sys-api/src/f4.rs b/drv/stm32xx-sys-api/src/f4.rs
new file mode 100644
index 0000000000..54ae3326f9
--- /dev/null
+++ b/drv/stm32xx-sys-api/src/f4.rs
@@ -0,0 +1,51 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+//! STM32F4 specifics
+
+use crate::periph;
+use userlib::FromPrimitive;
+
+/// Peripherals appear in "groups." All peripherals in a group are controlled
+/// from the same subset of registers in the RCC.
+///
+/// The reference manual lacks a term for this, so we made this one up. It would
+/// be tempting to refer to these as "buses," but in practice there are almost
+/// always more groups than there are buses, particularly on M0.
+///
+/// This is `pub` mostly for use inside driver-servers.
+#[derive(Copy, Clone, Debug, FromPrimitive)]
+#[repr(u8)]
+pub enum Group {
+    Ahb1,
+    Ahb2,
+    Ahb3,
+    Apb1,
+    Apb2,
+}
+
+/// Peripheral numbering.
+///
+/// Peripheral bit numbers per the STM32F4 documentation.
+#[derive(Copy, Clone, Eq, PartialEq, Debug)]
+#[repr(u32)]
+pub enum Peripheral {
+    GpioA = periph(Group::Ahb1, 0),
+    GpioB = periph(Group::Ahb1, 1),
+    GpioC = periph(Group::Ahb1, 2),
+    GpioD = periph(Group::Ahb1, 3),
+    GpioE = periph(Group::Ahb1, 4),
+    GpioF = periph(Group::Ahb1, 5),
+    GpioG = periph(Group::Ahb1, 6),
+    GpioH = periph(Group::Ahb1, 7),
+    GpioI = periph(Group::Ahb1, 8),
+    GpioJ = periph(Group::Ahb1, 9),
+    GpioK = periph(Group::Ahb1, 10),
+    Crc = periph(Group::Ahb1, 12),
+    Dma1 = periph(Group::Ahb1, 21),
+    Dma2 = periph(Group::Ahb1, 22),
+    Dma2d = periph(Group::Ahb1, 23),
+    EthMac = periph(Group::Ahb1, 25),
+    UsbOtgHs = periph(Group::Ahb1, 29),
+}
diff --git a/drv/stm32xx-sys-api/src/lib.rs b/drv/stm32xx-sys-api/src/lib.rs
index 5931eb2301..c3cf3916c0 100644
--- a/drv/stm32xx-sys-api/src/lib.rs
+++ b/drv/stm32xx-sys-api/src/lib.rs
@@ -13,6 +13,9 @@ cfg_if::cfg_if! {
     } else if #[cfg(feature = "family-stm32h7")] {
         mod h7;
         pub use self::h7::*;
+    } else if #[cfg(feature = "family-stm32f4")] {
+        mod f4;
+        pub use self::f4::*;
     } else {
         compile_error!("unsupported SoC family");
     }
diff --git a/drv/stm32xx-sys/Cargo.toml b/drv/stm32xx-sys/Cargo.toml
index 812da6d4d3..27fe0fef97 100644
--- a/drv/stm32xx-sys/Cargo.toml
+++ b/drv/stm32xx-sys/Cargo.toml
@@ -18,6 +18,7 @@ idol-runtime = { workspace = true }
 num-traits = { workspace = true }
 stm32g0 = { workspace = true, optional = true }
 stm32h7 = { workspace = true, optional = true }
+stm32f4 = { workspace = true, optional = true }
 zerocopy = { workspace = true }
 
 [build-dependencies]
@@ -36,6 +37,10 @@ g031 = ["family-stm32g0", "stm32g0/stm32g031", "drv-stm32xx-sys-api/g031", "drv-
 g070 = ["family-stm32g0", "stm32g0/stm32g070", "drv-stm32xx-sys-api/g070", "drv-stm32xx-gpio-common/model-stm32g070"]
 g0b1 = ["family-stm32g0", "stm32g0/stm32g0b1", "drv-stm32xx-sys-api/g0b1", "drv-stm32xx-gpio-common/model-stm32g0b1"]
 
+family-stm32f4 = ["stm32f4", "drv-stm32xx-uid/family-stm32f4"]
+f407 = ["family-stm32f4", "stm32f4/stm32f407", "drv-stm32xx-sys-api/f407", "drv-stm32xx-gpio-common/model-stm32f407"]
+f429 = ["family-stm32f4", "stm32f4/stm32f429", "drv-stm32xx-sys-api/f429", "drv-stm32xx-gpio-common/model-stm32f429"]
+
 no-ipc-counters = ["idol/no-counters"]
 no-panic = ["userlib/no-panic"]
 
diff --git a/drv/stm32xx-sys/src/main.rs b/drv/stm32xx-sys/src/main.rs
index 8e7849c9fb..8676a6a7dd 100644
--- a/drv/stm32xx-sys/src/main.rs
+++ b/drv/stm32xx-sys/src/main.rs
@@ -315,6 +315,14 @@ cfg_if! {
         use stm32h7::stm32h743 as device;
         #[cfg(feature = "h753")]
         use stm32h7::stm32h753 as device;
+    } else if #[cfg(feature = "family-stm32f4")] {
+        use stm32f4 as pac;
+
+        #[cfg(feature = "f407")]
+        use stm32f4::stm32f407 as device;
+
+        #[cfg(feature = "f429")]
+        use stm32f4::stm32f429 as device;
     } else {
         compile_error!("unsupported SoC family");
     }
@@ -504,6 +512,23 @@ fn main() -> ! {
                     .gpioken()
                     .set_bit()
             });
+        } else if #[cfg(feature = "family-stm32f4")] {
+            rcc.ahb1enr.write(|w| {
+                w.gpioaen().set_bit();
+                w.gpioben().set_bit();
+                w.gpiocen().set_bit();
+                w.gpioden().set_bit();
+                w.gpioeen().set_bit();
+                w.gpiofen().set_bit();
+                w.gpiogen().set_bit();
+                w.gpiohen().set_bit();
+                w.gpioien().set_bit();
+                #[cfg(feature = "f429")]
+                w.gpiojen().set_bit();
+                #[cfg(feature = "f429")]
+                w.gpioken().set_bit();
+                w
+            });
         }
     }
 
@@ -1220,6 +1245,71 @@ cfg_if! {
 
             Some(reason)
         }
+    } else if #[cfg(feature = "family-stm32f4")] {
+        fn enable_clock(
+            rcc: &device::rcc::RegisterBlock,
+            group: Group,
+            bit: u8,
+        ) {
+            match group {
+                Group::Ahb1 => unsafe { rcc.ahb1enr.set_bit(bit) },
+                Group::Ahb2 => unsafe { rcc.ahb2enr.set_bit(bit) },
+                Group::Ahb3 => unsafe { rcc.ahb3enr.set_bit(bit) },
+                Group::Apb1 => unsafe { rcc.apb1enr.set_bit(bit) },
+                Group::Apb2 => unsafe { rcc.apb2enr.set_bit(bit) },
+            }
+        }
+
+        fn disable_clock(
+            rcc: &device::rcc::RegisterBlock,
+            group: Group,
+            bit: u8,
+        ) {
+            match group {
+                Group::Ahb1 => unsafe { rcc.ahb1enr.clear_bit(bit) },
+                Group::Ahb2 => unsafe { rcc.ahb2enr.clear_bit(bit) },
+                Group::Ahb3 => unsafe { rcc.ahb3enr.clear_bit(bit) },
+                Group::Apb1 => unsafe { rcc.apb1enr.clear_bit(bit) },
+                Group::Apb2 => unsafe { rcc.apb2enr.clear_bit(bit) },
+            }
+        }
+
+        fn enter_reset(
+            rcc: &device::rcc::RegisterBlock,
+            group: Group,
+            bit: u8,
+        ) {
+            match group {
+                Group::Ahb1 => unsafe { rcc.ahb1rstr.set_bit(bit) },
+                Group::Ahb2 => unsafe { rcc.ahb2rstr.set_bit(bit) },
+                Group::Ahb3 => unsafe { rcc.ahb3rstr.set_bit(bit) },
+                Group::Apb1 => unsafe { rcc.apb1rstr.set_bit(bit) },
+                Group::Apb2 => unsafe { rcc.apb2rstr.set_bit(bit) },
+            }
+        }
+
+        fn leave_reset(
+            rcc: &device::rcc::RegisterBlock,
+            group: Group,
+            bit: u8,
+        ) {
+            match group {
+                Group::Ahb1 => unsafe { rcc.ahb1rstr.clear_bit(bit) },
+                Group::Ahb2 => unsafe { rcc.ahb2rstr.clear_bit(bit) },
+                Group::Ahb3 => unsafe { rcc.ahb3rstr.clear_bit(bit) },
+                Group::Apb1 => unsafe { rcc.apb1rstr.clear_bit(bit) },
+                Group::Apb2 => unsafe { rcc.apb2rstr.clear_bit(bit) },
+            }
+        }
+
+        #[cfg(not(feature = "test"))]
+        fn try_read_reset_reason(
+            rcc: &device::rcc::RegisterBlock,
+        ) -> Option<ResetReason> {
+            // TODO map to ResetReason cases
+            let bits = rcc.csr.read().bits();
+            Some(ResetReason::Other(bits))
+        }
     } else {
         compile_error!("unsupported SoC family");
     }
diff --git a/drv/stm32xx-uid/Cargo.toml b/drv/stm32xx-uid/Cargo.toml
index f17ea684b0..65c81ea12f 100644
--- a/drv/stm32xx-uid/Cargo.toml
+++ b/drv/stm32xx-uid/Cargo.toml
@@ -9,6 +9,7 @@ cfg-if = { workspace = true }
 [features]
 family-stm32g0 = []
 family-stm32h7 = []
+family-stm32f4 = []
 
 # This section is here to discourage RLS/rust-analyzer from doing test builds,
 # since test builds don't work for cross compilation.
diff --git a/drv/stm32xx-uid/src/lib.rs b/drv/stm32xx-uid/src/lib.rs
index 60a5fd8589..f3ee5679a0 100644
--- a/drv/stm32xx-uid/src/lib.rs
+++ b/drv/stm32xx-uid/src/lib.rs
@@ -15,6 +15,8 @@ cfg_if::cfg_if! {
         const UID_ADDR: u32 = 0x1FFF_7590;
     } else if #[cfg(feature = "family-stm32h7")] {
         const UID_ADDR: u32 = 0x1FF1_E800;
+    } else if #[cfg(feature = "family-stm32f4")] {
+        const UID_ADDR: u32 = 0x1FFF_7A10;
     } else {
         compile_error!("unsupported SoC family");
         const UID_ADDR: u32 = 0; // Prevents a second error below
diff --git a/drv/user-leds/Cargo.toml b/drv/user-leds/Cargo.toml
index 1c59060b37..4050e2cc83 100644
--- a/drv/user-leds/Cargo.toml
+++ b/drv/user-leds/Cargo.toml
@@ -10,7 +10,6 @@ idol-runtime.workspace = true
 lpc55-pac = { workspace = true, optional = true }
 num-traits.workspace = true
 stm32f3 = { workspace = true, optional = true, features = ["stm32f303"] }
-stm32f4 = { workspace = true, optional = true, features = ["stm32f407"] }
 zerocopy.workspace = true
 
 drv-lpc55-gpio-api = { path = "../lpc55-gpio-api", optional = true }
@@ -26,6 +25,7 @@ idol.workspace = true
 [features]
 stm32g0 = ["drv-stm32xx-sys-api/family-stm32g0"]
 stm32h7 = ["drv-stm32xx-sys-api/family-stm32h7"]
+stm32f4 = ["drv-stm32xx-sys-api/family-stm32f4"]
 lpc55 = ["lpc55-pac", "drv-lpc55-gpio-api"]
 panic-messages = ["userlib/panic-messages"]
 no-ipc-counters = ["idol/no-counters"]
diff --git a/drv/user-leds/src/main.rs b/drv/user-leds/src/main.rs
index 549fac5ea7..20ab0e4945 100644
--- a/drv/user-leds/src/main.rs
+++ b/drv/user-leds/src/main.rs
@@ -63,7 +63,7 @@ cfg_if::cfg_if! {
         }
     }
     // Target boards with 3 leds
-    else if #[cfg(any(target_board = "nucleo-h753zi", target_board = "nucleo-h743zi2"))] {
+    else if #[cfg(any(target_board = "nucleo-h753zi", target_board = "nucleo-h743zi2", target_board = "stm32f429-nucleo"))] {
         #[derive(enum_map::Enum, Copy, Clone, FromPrimitive)]
         enum Led {
             Zero = 0,
@@ -202,7 +202,7 @@ fn main() -> ! {
 // intermediary.
 
 cfg_if::cfg_if! {
-    if #[cfg(any(feature = "stm32f4", feature = "stm32f3"))] {
+    if #[cfg(any(feature = "stm32f3"))] {
         task_slot!(RCC, rcc_driver);
     }
 }
@@ -215,19 +215,12 @@ macro_rules! gpio {
         unsafe { &*stm32f3::stm32f303::GPIOE::ptr() }
     };
 }
-#[cfg(feature = "stm32f4")]
-macro_rules! gpio {
-    () => {
-        unsafe { &*stm32f4::stm32f407::GPIOD::ptr() }
-    };
-}
 
-#[cfg(any(feature = "stm32f3", feature = "stm32f4"))]
+#[cfg(any(feature = "stm32f3"))]
 fn enable_led_pins() {
     use zerocopy::AsBytes;
 
-    // This assumes an STM32F4DISCOVERY board, where the LEDs are on D12 and
-    // D13 OR an STM32F3DISCOVERY board, where the LEDs are on E8 and E9.
+    // This assumes a STM32F3DISCOVERY board, where the LEDs are on E8 and E9.
 
     // Contact the RCC driver to get power turned on for GPIOD/E.
     let rcc_driver = RCC.get_task_id();
@@ -235,8 +228,6 @@ fn enable_led_pins() {
 
     #[cfg(feature = "stm32f3")]
     let gpio_pnum: u32 = 21; // see bits in AHBENR
-    #[cfg(feature = "stm32f4")]
-    let gpio_pnum: u32 = 3; // see bits in AHB1ENR
 
     let (code, _) = userlib::sys_send(
         rcc_driver,
@@ -247,17 +238,15 @@ fn enable_led_pins() {
     );
     assert_eq!(code, 0);
 
-    // Now, directly manipulate GPIOD/E.
+    // Now, directly manipulate GPIOB/E.
     // TODO: this should go through a gpio driver probably.
     let gpio_moder = &gpio!().moder;
 
     #[cfg(feature = "stm32f3")]
     gpio_moder.modify(|_, w| w.moder8().output().moder9().output());
-    #[cfg(feature = "stm32f4")]
-    gpio_moder.modify(|_, w| w.moder12().output().moder13().output());
 }
 
-#[cfg(any(feature = "stm32f3", feature = "stm32f4"))]
+#[cfg(any(feature = "stm32f3"))]
 fn led_on(led: Led) {
     let gpio = gpio!();
 
@@ -266,15 +255,10 @@ fn led_on(led: Led) {
         Led::Zero => gpio.bsrr.write(|w| w.bs8().set_bit()),
         #[cfg(feature = "stm32f3")]
         Led::One => gpio.bsrr.write(|w| w.bs9().set_bit()),
-
-        #[cfg(feature = "stm32f4")]
-        Led::Zero => gpio.bsrr.write(|w| w.bs12().set_bit()),
-        #[cfg(feature = "stm32f4")]
-        Led::One => gpio.bsrr.write(|w| w.bs13().set_bit()),
     }
 }
 
-#[cfg(any(feature = "stm32f3", feature = "stm32f4"))]
+#[cfg(any(feature = "stm32f3"))]
 fn led_off(led: Led) {
     let gpio = gpio!();
 
@@ -283,15 +267,10 @@ fn led_off(led: Led) {
         Led::Zero => gpio.bsrr.write(|w| w.br8().set_bit()),
         #[cfg(feature = "stm32f3")]
         Led::One => gpio.bsrr.write(|w| w.br9().set_bit()),
-
-        #[cfg(feature = "stm32f4")]
-        Led::Zero => gpio.bsrr.write(|w| w.br12().set_bit()),
-        #[cfg(feature = "stm32f4")]
-        Led::One => gpio.bsrr.write(|w| w.br13().set_bit()),
     }
 }
 
-#[cfg(any(feature = "stm32f3", feature = "stm32f4"))]
+#[cfg(any(feature = "stm32f3"))]
 fn led_toggle(led: Led) {
     let gpio = gpio!();
 
@@ -312,23 +291,6 @@ fn led_toggle(led: Led) {
                 gpio.bsrr.write(|w| w.bs9().set_bit())
             }
         }
-
-        #[cfg(feature = "stm32f4")]
-        Led::Zero => {
-            if gpio.odr.read().odr12().bit() {
-                gpio.bsrr.write(|w| w.br12().set_bit())
-            } else {
-                gpio.bsrr.write(|w| w.bs12().set_bit())
-            }
-        }
-        #[cfg(feature = "stm32f4")]
-        Led::One => {
-            if gpio.odr.read().odr13().bit() {
-                gpio.bsrr.write(|w| w.br13().set_bit())
-            } else {
-                gpio.bsrr.write(|w| w.bs13().set_bit())
-            }
-        }
     }
 }
 
@@ -575,6 +537,100 @@ fn led_toggle(led: Led) {
     sys.gpio_toggle(pinset.port, pinset.pin_mask).unwrap_lite();
 }
 
+///////////////////////////////////////////////////////////////////////////////
+// The STM32F4 specific bits.
+//
+
+cfg_if::cfg_if! {
+    if #[cfg(feature = "stm32f4")] {
+        task_slot!(SYS, sys);
+
+        const LEDS: &[(drv_stm32xx_sys_api::PinSet, bool)] =
+        {
+            cfg_if::cfg_if! {
+                if #[cfg(target_board = "stm32f429-nucleo")] {
+                    &[
+                        (drv_stm32xx_sys_api::Port::B.pin(0), true),
+                        (drv_stm32xx_sys_api::Port::B.pin(7), true),
+                        (drv_stm32xx_sys_api::Port::B.pin(14), true)
+                    ]
+                } else if #[cfg(target_board = "stm32f4-discovery")] {
+                    &[
+                        (drv_stm32xx_sys_api::Port::D.pin(12), true),
+                        (drv_stm32xx_sys_api::Port::D.pin(13), true),
+                    ]
+                } else {
+                    compile_error!("Unknown STM32F4 board")
+                }
+            }
+        };
+    }
+}
+
+#[cfg(feature = "stm32f4")]
+fn enable_led_pins() {
+    use drv_stm32xx_sys_api::*;
+
+    let sys = SYS.get_task_id();
+    let sys = Sys::from(sys);
+
+    for &(pinset, active_low) in LEDS {
+        // Make sure LEDs are initially off.
+        sys.gpio_set_to(pinset, active_low);
+        // Make them outputs.
+        sys.gpio_configure_output(
+            pinset,
+            OutputType::PushPull,
+            Speed::High,
+            Pull::None,
+        );
+    }
+}
+
+#[cfg(feature = "stm32f4")]
+fn led_info(led: Led) -> (drv_stm32xx_sys_api::PinSet, bool) {
+    match led {
+        Led::Zero => LEDS[0],
+        Led::One => LEDS[1],
+        #[cfg(target_board = "stm32f429-nucleo")]
+        Led::Two => LEDS[2],
+    }
+}
+
+#[cfg(feature = "stm32f4")]
+fn led_on(led: Led) {
+    use drv_stm32xx_sys_api::*;
+
+    let sys = SYS.get_task_id();
+    let sys = Sys::from(sys);
+
+    let (pinset, active_low) = led_info(led);
+    sys.gpio_set_to(pinset, !active_low);
+}
+
+#[cfg(feature = "stm32f4")]
+fn led_off(led: Led) {
+    use drv_stm32xx_sys_api::*;
+
+    let sys = SYS.get_task_id();
+    let sys = Sys::from(sys);
+
+    let (pinset, active_low) = led_info(led);
+
+    sys.gpio_set_to(pinset, active_low);
+}
+
+#[cfg(feature = "stm32f4")]
+fn led_toggle(led: Led) {
+    use drv_stm32xx_sys_api::*;
+
+    let sys = SYS.get_task_id();
+    let sys = Sys::from(sys);
+
+    let pinset = led_info(led).0;
+    sys.gpio_toggle(pinset.port, pinset.pin_mask).unwrap_lite();
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // The LPC55 specific bits.