diff --git a/src/slcr.rs b/src/slcr.rs
index 2dcbb051..4d814c12 100644
--- a/src/slcr.rs
+++ b/src/slcr.rs
@@ -1,5 +1,6 @@
-#[allow(unused)]
+///! Register definitions for System Level Control
 
+use volatile_register::{RO, WO, RW};
 use crate::{register, register_bit, register_bits, register_at, regs::RegisterW, regs::RegisterRW};
 
 pub enum PllSource {
@@ -8,45 +9,228 @@ pub enum PllSource {
     DdrPll = 0b11,
 }
 
-pub fn with_slcr<F: FnMut() -> R, R>(mut f: F) -> R {
-    unsafe { SlcrUnlock::new() }.unlock();
-    let r = f();
-    unsafe { SlcrLock::new() }.lock();
-    r
+#[repr(C)]
+pub struct RegisterBlock {
+    pub scl: RW<u32>,
+    pub slcr_lock: SlcrLock,
+    pub slcr_unlock: SlcrUnlock,
+    pub slcr_locksta: RO<u32>,
+    reserved0: [u32; 60],
+    pub arm_pll_ctrl: RW<u32>,
+    pub ddr_pll_ctrl: RW<u32>,
+    pub io_pll_ctrl: RW<u32>,
+    pub pll_status: RO<u32>,
+    pub arm_pll_cfg: RW<u32>,
+    pub ddr_pll_cfg: RW<u32>,
+    pub io_pll_cfg: RW<u32>,
+    reserved1: [u32; 1],
+    pub arm_clk_ctrl: RW<u32>,
+    pub ddr_clk_ctrl: RW<u32>,
+    pub dci_clk_ctrl: RW<u32>,
+    pub aper_clk_ctrl: AperClkCtrl,
+    pub usb0_clk_ctrl: RW<u32>,
+    pub usb1_clk_ctrl: RW<u32>,
+    pub gem0_rclk_ctrl: RW<u32>,
+    pub gem1_rclk_ctrl: RW<u32>,
+    pub gem0_clk_ctrl: RW<u32>,
+    pub gem1_clk_ctrl: RW<u32>,
+    pub smc_clk_ctrl: RW<u32>,
+    pub lqspi_clk_ctrl: RW<u32>,
+    pub sdio_clk_ctrl: RW<u32>,
+    pub uart_clk_ctrl: UartClkCtrl,
+    pub spi_clk_ctrl: RW<u32>,
+    pub can_clk_ctrl: RW<u32>,
+    pub can_mioclk_ctrl: RW<u32>,
+    pub dbg_clk_ctrl: RW<u32>,
+    pub pcap_clk_ctrl: RW<u32>,
+    pub topsw_clk_ctrl: RW<u32>,
+    pub fpga0_clk_ctrl: RW<u32>,
+    pub fpga0_thr_ctrl: RW<u32>,
+    pub fpga0_thr_cnt: RW<u32>,
+    pub fpga0_thr_sta: RO<u32>,
+    pub fpga1_clk_ctrl: RW<u32>,
+    pub fpga1_thr_ctrl: RW<u32>,
+    pub fpga1_thr_cnt: RW<u32>,
+    pub fpga1_thr_sta: RO<u32>,
+    pub fpga2_clk_ctrl: RW<u32>,
+    pub fpga2_thr_ctrl: RW<u32>,
+    pub fpga2_thr_cnt: RW<u32>,
+    pub fpga2_thr_sta: RO<u32>,
+    pub fpga3_clk_ctrl: RW<u32>,
+    pub fpga3_thr_ctrl: RW<u32>,
+    pub fpga3_thr_cnt: RW<u32>,
+    pub fpga3_thr_sta: RO<u32>,
+    reserved2: [u32; 5],
+    pub clk_621_true: RW<u32>,
+    reserved3: [u32; 14],
+    pub pss_rst_ctrl: RW<u32>,
+    pub ddr_rst_ctrl: RW<u32>,
+    pub topsw_rst_ctrl: RW<u32>,
+    pub dmac_rst_ctrl: RW<u32>,
+    pub usb_rst_ctrl: RW<u32>,
+    pub gem_rst_ctrl: RW<u32>,
+    pub sdio_rst_ctrl: RW<u32>,
+    pub spi_rst_ctrl: RW<u32>,
+    pub can_rst_ctrl: RW<u32>,
+    pub i2c_rst_ctrl: RW<u32>,
+    pub uart_rst_ctrl: UartRstCtrl,
+    pub gpio_rst_ctrl: RW<u32>,
+    pub lqspi_rst_ctrl: RW<u32>,
+    pub smc_rst_ctrl: RW<u32>,
+    pub ocm_rst_ctrl: RW<u32>,
+    reserved4: [u32; 1],
+    pub fpga_rst_ctrl: RW<u32>,
+    pub a9_cpu_rst_ctrl: RW<u32>,
+    reserved5: [u32; 1],
+    pub rs_awdt_ctrl: RW<u32>,
+    reserved6: [u32; 2],
+    pub reboot_status: RW<u32>,
+    pub boot_mode: RW<u32>,
+    reserved7: [u32; 40],
+    pub apu_ctrl: RW<u32>,
+    pub wdt_clk_sel: RW<u32>,
+    reserved8: [u32; 78],
+    pub tz_dma_ns: RW<u32>,
+    pub tz_dma_irq_ns: RW<u32>,
+    pub tz_dma_periph_ns: RW<u32>,
+    reserved9: [u32; 57],
+    pub pss_idcode: RW<u32>,
+    reserved10: [u32; 51],
+    pub ddr_urgent: RW<u32>,
+    reserved11: [u32; 2],
+    pub ddr_cal_start: RW<u32>,
+    reserved12: [u32; 1],
+    pub ddr_ref_start: RW<u32>,
+    pub ddr_cmd_sta: RW<u32>,
+    pub ddr_urgent_sel: RW<u32>,
+    pub ddr_dfi_status: RW<u32>,
+    reserved13: [u32; 55],
+    pub mio_pin_00: RW<u32>,
+    pub mio_pin_01: RW<u32>,
+    pub mio_pin_02: RW<u32>,
+    pub mio_pin_03: RW<u32>,
+    pub mio_pin_04: RW<u32>,
+    pub mio_pin_05: RW<u32>,
+    pub mio_pin_06: RW<u32>,
+    pub mio_pin_07: RW<u32>,
+    pub mio_pin_08: RW<u32>,
+    pub mio_pin_09: RW<u32>,
+    pub mio_pin_10: RW<u32>,
+    pub mio_pin_11: RW<u32>,
+    pub mio_pin_12: RW<u32>,
+    pub mio_pin_13: RW<u32>,
+    pub mio_pin_14: RW<u32>,
+    pub mio_pin_15: RW<u32>,
+    pub mio_pin_16: RW<u32>,
+    pub mio_pin_17: RW<u32>,
+    pub mio_pin_18: RW<u32>,
+    pub mio_pin_19: RW<u32>,
+    pub mio_pin_20: RW<u32>,
+    pub mio_pin_21: RW<u32>,
+    pub mio_pin_22: RW<u32>,
+    pub mio_pin_23: RW<u32>,
+    pub mio_pin_24: RW<u32>,
+    pub mio_pin_25: RW<u32>,
+    pub mio_pin_26: RW<u32>,
+    pub mio_pin_27: RW<u32>,
+    pub mio_pin_28: RW<u32>,
+    pub mio_pin_29: RW<u32>,
+    pub mio_pin_30: RW<u32>,
+    pub mio_pin_31: RW<u32>,
+    pub mio_pin_32: RW<u32>,
+    pub mio_pin_33: RW<u32>,
+    pub mio_pin_34: RW<u32>,
+    pub mio_pin_35: RW<u32>,
+    pub mio_pin_36: RW<u32>,
+    pub mio_pin_37: RW<u32>,
+    pub mio_pin_38: RW<u32>,
+    pub mio_pin_39: RW<u32>,
+    pub mio_pin_40: RW<u32>,
+    pub mio_pin_41: RW<u32>,
+    pub mio_pin_42: RW<u32>,
+    pub mio_pin_43: RW<u32>,
+    pub mio_pin_44: RW<u32>,
+    pub mio_pin_45: RW<u32>,
+    pub mio_pin_46: RW<u32>,
+    pub mio_pin_47: RW<u32>,
+    pub mio_pin_48: MioPin48,
+    pub mio_pin_49: MioPin49,
+    pub mio_pin_50: RW<u32>,
+    pub mio_pin_51: RW<u32>,
+    pub mio_pin_52: RW<u32>,
+    pub mio_pin_53: RW<u32>,
+    reserved14: [u32; 11],
+    pub mio_loopback: RW<u32>,
+    reserved15: [u32; 1],
+    pub mio_mst_tri0: RW<u32>,
+    pub mio_mst_tri1: RW<u32>,
+    reserved16: [u32; 7],
+    pub sd0_wp_cd_sel: RW<u32>,
+    pub sd1_wp_cd_sel: RW<u32>,
+    reserved17: [u32; 50],
+    pub lvl_shftr_en: RW<u32>,
+    reserved18: [u32; 3],
+    pub ocm_cfg: RW<u32>,
+    reserved19: [u32; 123],
+    pub gpiob_ctrl: RW<u32>,
+    pub gpiob_cfg_cmos18: RW<u32>,
+    pub gpiob_cfg_cmos25: RW<u32>,
+    pub gpiob_cfg_cmos33: RW<u32>,
+    reserved20: [u32; 1],
+    pub gpiob_cfg_hstl: RW<u32>,
+    pub gpiob_drvr_bias_ctrl: RW<u32>,
+    reserved21: [u32; 9],
+    pub ddriob_addr1: RW<u32>,
+    pub ddriob_data0: RW<u32>,
+    pub ddriob_data1: RW<u32>,
+    pub ddriob_diff0: RW<u32>,
+    pub ddriob_diff1: RW<u32>,
+    pub ddriob_clock: RW<u32>,
+    pub w_addr: RW<u32>,
+    pub w_data: RW<u32>,
+    pub w_diff: RW<u32>,
+    pub w_clock: RW<u32>,
+    pub ddriob_ddr_ctrl: RW<u32>,
+    pub ddriob_dci_ctrl: RW<u32>,
+    pub ddriob_dci_status: RW<u32>,
+}
+register_at!(RegisterBlock, 0xF8000000, new);
+
+impl RegisterBlock {
+    pub fn unlocked<F: FnMut(&Self) -> R, R>(mut f: F) -> R {
+        let self_ = Self::new();
+        self_.slcr_unlock.unlock();
+        let r = f(&self_);
+        self_.slcr_lock.lock();
+        r
+    }
 }
 
 register!(slcr_lock, SlcrLock, WO, u32);
 register_bits!(slcr_lock, lock_key, u16, 0, 15);
-register_at!(SlcrLock, 0xF8000004, new);
 impl SlcrLock {
     pub fn lock(&self) {
-        unsafe {
-            self.write(
-                Self::zeroed()
-                    .lock_key(0x767B)
-            );
-        }
+        self.write(
+            Self::zeroed()
+                .lock_key(0x767B)
+        );
     }
 }
 
 register!(slcr_unlock, SlcrUnlock, WO, u32);
 register_bits!(slcr_unlock, unlock_key, u16, 0, 15);
-register_at!(SlcrUnlock, 0xF8000008, new);
 impl SlcrUnlock {
     pub fn unlock(&self) {
-        unsafe {
-            self.write(
-                Self::zeroed()
-                    .unlock_key(0xDF0D)
-            );
-        }
+        self.write(
+            Self::zeroed()
+                .unlock_key(0xDF0D)
+        );
     }
 }
 
 register!(aper_clk_ctrl, AperClkCtrl, RW, u32);
 register_bit!(aper_clk_ctrl, uart1_cpu_1xclkact, 21);
 register_bit!(aper_clk_ctrl, uart0_cpu_1xclkact, 20);
-register_at!(AperClkCtrl, 0xF800012C, new);
 impl AperClkCtrl {
     pub fn enable_uart0(&self) {
         self.modify(|_, w| w.uart0_cpu_1xclkact(true));
@@ -117,3 +301,29 @@ impl UartRstCtrl {
         );
     }
 }
+
+/// Used for MioPin*.io_type
+pub enum IoBufferType {
+    Lvcmos18 = 0b001,
+    Lvcmos25 = 0b010,
+    Lvcmos33 = 0b011,
+    Hstl     = 0b100,
+}
+
+macro_rules! mio_pin_register {
+    ($mod_name: ident, $struct_name: ident) => (
+        register!($mod_name, $struct_name, RW, u32);
+        register_bit!($mod_name, disable_rcvr, 13);
+        register_bit!($mod_name, pullup, 12);
+        register_bits!($mod_name, io_type, u8, 9, 11);
+        register_bit!($mod_name, speed, 8);
+        register_bits!($mod_name, l3_sel, u8, 5, 7);
+        register_bits!($mod_name, l2_sel, u8, 3, 4);
+        register_bit!($mod_name, l1_sel, 2);
+        register_bit!($mod_name, l0_sel, 1);
+        register_bit!($mod_name, tri_enable, 0);
+    );
+}
+
+mio_pin_register!(mio_pin_48, MioPin48);
+mio_pin_register!(mio_pin_49, MioPin49);
diff --git a/src/uart/mod.rs b/src/uart/mod.rs
index 93f0d9ed..64206f54 100644
--- a/src/uart/mod.rs
+++ b/src/uart/mod.rs
@@ -4,6 +4,7 @@ use core::fmt;
 use volatile_register::RW;
 
 use crate::regs::*;
+use crate::slcr;
 
 mod regs;
 mod baud_rate_gen;
@@ -18,24 +19,28 @@ pub struct Uart {
 
 impl Uart {
     pub fn uart1(baudrate: u32) -> Self {
-        super::slcr::with_slcr(|| {
-            let uart_rst_ctrl = super::slcr::UartRstCtrl::new();
-            uart_rst_ctrl.reset_uart1();
+        slcr::RegisterBlock::unlocked(|slcr| {
+            slcr.uart_rst_ctrl.reset_uart1();
 
             // Route UART 1 RxD/TxD Signals to MIO Pins
-            unsafe {
-                // TX pin
-                let mio_pin_48 = &*(0xF80007C0 as *const RW<u32>);
-                mio_pin_48.write(0x0000_12E0);
-                // RX pin
-                let mio_pin_49 = &*(0xF80007C4 as *const RW<u32>);
-                mio_pin_49.write(0x0000_12E1);
-            }
+            // TX pin
+            slcr.mio_pin_48.write(
+                slcr::MioPin48::zeroed()
+                    .l3_sel(0b111)
+                    .io_type(0b001)
+                    .pullup(true)
+            );
+            // RX pin
+            slcr.mio_pin_49.write(
+                slcr::MioPin49::zeroed()
+                    .tri_enable(true)
+                    .l3_sel(0b111)
+                    .io_type(0b001)
+                    .pullup(true)
+            );
 
-            let aper_clk_ctrl = super::slcr::AperClkCtrl::new();
-            aper_clk_ctrl.enable_uart1();
-            let uart_clk_ctrl = super::slcr::UartClkCtrl::new();
-            uart_clk_ctrl.enable_uart1();
+            slcr.aper_clk_ctrl.enable_uart1();
+            slcr.uart_clk_ctrl.enable_uart1();
         });
         let self_ = Uart {
             regs: regs::RegisterBlock::uart1(),