tcp_client: rm print

This commit is contained in:
occheung 2020-09-04 13:31:11 +08:00
parent 79ce44552b
commit 4c88c31aca

View File

@ -1,195 +1,182 @@
#![no_std]
#![no_main] #![no_main]
#![no_std]
use smoltcp as net; use core::sync::atomic::{AtomicU32, Ordering};
use stm32h7_ethernet as ethernet;
use stm32h7xx_hal::{gpio::Speed, prelude::*, spi, pac};
use embedded_hal::{blocking::spi::Transfer};
use heapless::{consts, String}; // extern crate cortex_m;
use panic_semihosting as _;
use cortex_m; use cortex_m;
use cortex_m::asm::nop;
use cortex_m_rt::{ use cortex_m_rt::{
entry, entry,
exception, exception,
}; };
use cortex_m_semihosting::hprintln; use cortex_m_semihosting::hprintln;
use panic_halt as _; extern crate smoltcp;
use rtic::cyccnt::{Instant, U32Ext}; // Ethernet crate for STM32H7 has been merged into HAL in the latest commit
extern crate stm32h7_ethernet as ethernet;
use minimq::{ use stm32h7xx_hal::gpio::Speed;
embedded_nal::{IpAddr, Ipv4Addr}, use stm32h7xx_hal::hal::digital::v2::{
MqttClient, QoS, OutputPin,
InputPin,
}; };
use stm32h7xx_hal::rcc::CoreClocks;
use stm32h7xx_hal::{pac, prelude::*, spi, stm32, stm32::interrupt};
use Speed::*;
use firmware::nal_tcp_client::{NetworkStack, NetStorage, NetworkInterface}; use libm::round;
use firmware::{Urukul};
use firmware::cpld::{CPLD};
static mut NET_STORE: NetStorage = NetStorage { use core::{
// Placeholder for the real IP address, which is initialized at runtime. str,
ip_addrs: [net::wire::IpCidr::Ipv6( fmt::Write
net::wire::Ipv6Cidr::SOLICITED_NODE_PREFIX,
)],
neighbor_cache: [None; 8],
}; };
use core::mem::uninitialized;
use smoltcp::wire::{EthernetAddress, IpAddress, IpCidr, Ipv4Address};
use smoltcp::iface::{NeighborCache, EthernetInterfaceBuilder, Routes};
use smoltcp::socket::SocketSet;
use smoltcp::socket::{SocketHandle, TcpSocket, TcpSocketBuffer};
use smoltcp::time::{Duration, Instant};
use embedded_nal::TcpStack;
use firmware;
use firmware::{
attenuator::Attenuator,
config_register::{
ConfigRegister,
CFGMask,
StatusMask,
},
dds::{
DDS,
DDSCFRMask,
},
cpld::{
CPLD,
},
Urukul,
};
use scpi::prelude::*;
/// Configure SYSTICK for 1ms timebase
fn systick_init(syst: &mut stm32::SYST, clocks: CoreClocks) {
let c_ck_mhz = clocks.c_ck().0 / 1_000_000;
let syst_calib = 0x3E8;
syst.set_clock_source(cortex_m::peripheral::syst::SystClkSource::Core);
syst.set_reload((syst_calib * c_ck_mhz) - 1);
syst.enable_interrupt();
syst.enable_counter();
}
/// ======================================================================
/// Entry point
/// ======================================================================
/// TIME is an atomic u32 that counts milliseconds. Although not used
/// here, it is very useful to have for network protocols
static TIME: AtomicU32 = AtomicU32::new(0);
/// Locally administered MAC address
const MAC_ADDRESS: [u8; 6] = [0x02, 0x00, 0x11, 0x22, 0x33, 0x44];
/// Ethernet descriptor rings are a global singleton
#[link_section = ".sram3.eth"] #[link_section = ".sram3.eth"]
static mut DES_RING: ethernet::DesRing = ethernet::DesRing::new(); static mut DES_RING: ethernet::DesRing = ethernet::DesRing::new();
macro_rules! add_socket { // Theoratical maximum number of socket that can be handled
($sockets:ident, $tx_storage:ident, $rx_storage:ident) => { const SOCKET_COUNT: usize = 2;
let mut $rx_storage = [0; 4096];
let mut $tx_storage = [0; 4096];
let tcp_socket = { // Give buffer sizes of transmitting and receiving TCP packets
let tx_buffer = net::socket::TcpSocketBuffer::new(&mut $tx_storage[..]); const BUFFER_SIZE: usize = 2048;
let rx_buffer = net::socket::TcpSocketBuffer::new(&mut $rx_storage[..]);
net::socket::TcpSocket::new(tx_buffer, rx_buffer)
};
let _handle = $sockets.add(tcp_socket);
};
}
pub type UrukulType = Urukul<
firmware::spi_slave::SPISlave<
'static,
firmware::cpld::CPLD<
stm32h7xx_hal::spi::Spi<stm32h7xx_hal::device::SPI1>,
stm32h7xx_hal::gpio::gpiob::PB12<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioa::PA15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioc::PC7<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpiob::PB15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>
>,
stm32h7xx_hal::spi::Spi<stm32h7xx_hal::device::SPI1>,
stm32h7xx_hal::gpio::gpiob::PB12<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioa::PA15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioc::PC7<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpiob::PB15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>
>
>;
pub type CPLDType = CPLD<
stm32h7xx_hal::spi::Spi<stm32h7xx_hal::device::SPI1>,
stm32h7xx_hal::gpio::gpiob::PB12<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioa::PA15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioc::PC7<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpiob::PB15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>
>;
pub type IoUpdateType = stm32h7xx_hal::gpio::gpiob::PB15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>;
pub type SpiType = stm32h7xx_hal::spi::Spi<stm32h7xx_hal::device::SPI1, u8>;
pub type PartsType = firmware::spi_slave::Parts<
'static,
firmware::cpld::CPLD<
stm32h7xx_hal::spi::Spi<stm32h7xx_hal::device::SPI1>,
stm32h7xx_hal::gpio::gpiob::PB12<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioa::PA15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioc::PC7<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpiob::PB15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>
>,
stm32h7xx_hal::spi::Spi<stm32h7xx_hal::device::SPI1>,
stm32h7xx_hal::gpio::gpiob::PB12<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioa::PA15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpioc::PC7<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>,
stm32h7xx_hal::gpio::gpiob::PB15<stm32h7xx_hal::gpio::Output<stm32h7xx_hal::gpio::PushPull>>
>;
// the program entry point
#[entry] #[entry]
fn main() -> ! { fn main() -> ! {
let mut cp = cortex_m::Peripherals::take().unwrap(); let mut cp = cortex_m::Peripherals::take().unwrap();
let dp = pac::Peripherals::take().unwrap(); let dp = pac::Peripherals::take().unwrap();
cp.DWT.enable_cycle_counter(); // Initialise power...
// Enable SRAM3 for the descriptor ring.
dp.RCC.ahb2enr.modify(|_, w| w.sram3en().set_bit());
let rcc = dp.RCC.constrain();
let pwr = dp.PWR.constrain(); let pwr = dp.PWR.constrain();
let vos = pwr.freeze(); let vos = pwr.freeze();
let ccdr = rcc // Initialise SRAM3
.sysclk(400.mhz()) dp.RCC.ahb2enr.modify(|_, w| w.sram3en().set_bit());
.hclk(200.mhz())
.per_ck(100.mhz())
.pll1_q_ck(48.mhz()) // for SPI
.pll2_p_ck(100.mhz())
.pll2_q_ck(100.mhz())
.freeze(vos, &dp.SYSCFG);
// Initialise clocks...
let rcc = dp.RCC.constrain();
let ccdr = rcc
.sys_ck(200.mhz())
.hclk(200.mhz())
.pll1_r_ck(100.mhz()) // for TRACECK
.pll1_q_ck(48.mhz()) // for SPI
.freeze(vos, &dp.SYSCFG);
// Get the delay provider.
let delay = cp.SYST.delay(ccdr.clocks);
// Initialise system...
cp.SCB.invalidate_icache();
cp.SCB.enable_icache();
// TODO: ETH DMA coherence issues
// cp.SCB.enable_dcache(&mut cp.CPUID);
cp.DWT.enable_cycle_counter();
// Initialise IO...
let gpioa = dp.GPIOA.split(ccdr.peripheral.GPIOA); let gpioa = dp.GPIOA.split(ccdr.peripheral.GPIOA);
let gpiob = dp.GPIOB.split(ccdr.peripheral.GPIOB); let gpiob = dp.GPIOB.split(ccdr.peripheral.GPIOB);
let gpioc = dp.GPIOC.split(ccdr.peripheral.GPIOC); let gpioc = dp.GPIOC.split(ccdr.peripheral.GPIOC);
let gpiod = dp.GPIOD.split(ccdr.peripheral.GPIOD); let gpiod = dp.GPIOD.split(ccdr.peripheral.GPIOD);
let gpioe = dp.GPIOE.split(ccdr.peripheral.GPIOE); let gpioe = dp.GPIOE.split(ccdr.peripheral.GPIOE);
let gpiof = dp.GPIOF.split(ccdr.peripheral.GPIOF); let gpiof = dp.GPIOF.split(ccdr.peripheral.GPIOF);
let gpiog = dp.GPIOG.split(ccdr.peripheral.GPIOG); let gpiog = dp.GPIOG.split(ccdr.peripheral.GPIOG);
// let mut link_led = gpiob.pb0.into_push_pull_output(); // LED1, green
// let mut status_led = gpioe.pe1.into_push_pull_output(); // LD2, yellow
// let mut listen_led = gpiob.pb14.into_push_pull_output(); // LD3, red
// link_led.set_low().ok();
// status_led.set_low().ok();
// listen_led.set_low().ok();
// Configure ethernet IO // Setup CDONE for checking
{ let fpga_cdone = gpiod.pd15.into_pull_up_input();
let _rmii_refclk = gpioa.pa1.into_alternate_af11().set_speed(Speed::VeryHigh);
let _rmii_mdio = gpioa.pa2.into_alternate_af11().set_speed(Speed::VeryHigh);
let _rmii_mdc = gpioc.pc1.into_alternate_af11().set_speed(Speed::VeryHigh);
let _rmii_crs_dv = gpioa.pa7.into_alternate_af11().set_speed(Speed::VeryHigh);
let _rmii_rxd0 = gpioc.pc4.into_alternate_af11().set_speed(Speed::VeryHigh);
let _rmii_rxd1 = gpioc.pc5.into_alternate_af11().set_speed(Speed::VeryHigh);
let _rmii_tx_en = gpiog.pg11.into_alternate_af11().set_speed(Speed::VeryHigh);
let _rmii_txd0 = gpiog.pg13.into_alternate_af11().set_speed(Speed::VeryHigh);
let _rmii_txd1 = gpiob.pb13.into_alternate_af11().set_speed(Speed::VeryHigh);
}
// Configure ethernet match fpga_cdone.is_high() {
let mut net_interface = { Ok(true) => hprintln!("FPGA is ready."),
let mac_addr = net::wire::EthernetAddress([0xAC, 0x6F, 0x7A, 0xDE, 0xD6, 0xC8]); Ok(_) => hprintln!("FPGA is in reset state."),
let (eth_dma, _eth_mac) = unsafe { Err(_) => hprintln!("Error: Cannot read C_DONE"),
ethernet::ethernet_init( }.unwrap();
dp.ETHERNET_MAC,
dp.ETHERNET_MTL, // Setup Urukul
dp.ETHERNET_DMA, /*
&mut DES_RING, * Using SPI1, AF5
mac_addr.clone(), * SCLK -> PA5
) * MOSI -> PB5
}; * MISO -> PA6
* CS -> 0: PB12, 1: PA15, 2: PC7
*/
unsafe { ethernet::enable_interrupt() }
let store = unsafe { &mut NET_STORE };
store.ip_addrs[0] = net::wire::IpCidr::new(net::wire::IpAddress::v4(192, 168, 1, 200), 24);
let neighbor_cache = net::iface::NeighborCache::new(&mut store.neighbor_cache[..]);
net::iface::EthernetInterfaceBuilder::new(eth_dma)
.ethernet_addr(mac_addr)
.neighbor_cache(neighbor_cache)
.ip_addrs(&mut store.ip_addrs[..])
.finalize()
};
/*
* Using SPI1, AF5
* SCLK -> PA5
* MOSI -> PB5
* MISO -> PA6
* CS -> 0: PB12, 1: PA15, 2: PC7
* I/O_Update -> PB15
*/
let sclk = gpioa.pa5.into_alternate_af5(); let sclk = gpioa.pa5.into_alternate_af5();
let mosi = gpiob.pb5.into_alternate_af5(); let mosi = gpiob.pb5.into_alternate_af5();
let miso = gpioa.pa6.into_alternate_af5(); let miso = gpioa.pa6.into_alternate_af5();
let (cs0, cs1, cs2) = ( let (cs0, cs1, cs2) = (
gpiob.pb12.into_push_pull_output(), gpiob.pb12.into_push_pull_output(),
gpioa.pa15.into_push_pull_output(), gpioa.pa15.into_push_pull_output(),
gpioc.pc7.into_push_pull_output(), gpioc.pc7.into_push_pull_output(),
); );
let io_update = gpiob.pb15.into_push_pull_output(); /*
* I/O_Update -> PB15
*/
let io_update = gpiob.pb15.into_push_pull_output();
let spi = dp.SPI1.spi( let spi = dp.SPI1.spi(
(sclk, miso, mosi), (sclk, miso, mosi),
@ -199,63 +186,201 @@ fn main() -> ! {
&ccdr.clocks, &ccdr.clocks,
); );
let cpld = CPLD::new(spi, (cs0, cs1, cs2), io_update); let switch = CPLD::new(spi, (cs0, cs1, cs2), io_update);
let parts = cpld.split(); let parts = switch.split();
let mut urukul = Urukul::new(
let urukul = Urukul::new(
parts.spi1, parts.spi2, parts.spi3, parts.spi4, parts.spi5, parts.spi6, parts.spi7, parts.spi1, parts.spi2, parts.spi3, parts.spi4, parts.spi5, parts.spi6, parts.spi7,
[25_000_000, 25_000_000, 25_000_000, 25_000_000] [25_000_000, 25_000_000, 25_000_000, 25_000_000]
); );
cp.SCB.enable_icache(); // Setup ethernet pins
setup_ethernet_pins(
gpioa.pa1, gpioa.pa2, gpioc.pc1, gpioa.pa7, gpioc.pc4,
gpioc.pc5, gpiog.pg11, gpiog.pg13, gpiob.pb13
);
let mut time: u32 = 0; // Initialise ethernet...
let mut next_ms = Instant::now(); assert_eq!(ccdr.clocks.hclk().0, 200_000_000); // HCLK 200MHz
assert_eq!(ccdr.clocks.pclk1().0, 100_000_000); // PCLK 100MHz
assert_eq!(ccdr.clocks.pclk2().0, 100_000_000); // PCLK 100MHz
assert_eq!(ccdr.clocks.pclk4().0, 100_000_000); // PCLK 100MHz
next_ms += 400_00.cycles(); let mac_addr = smoltcp::wire::EthernetAddress::from_bytes(&MAC_ADDRESS);
let (_eth_dma, mut eth_mac) = unsafe {
ethernet::ethernet_init(
dp.ETHERNET_MAC,
dp.ETHERNET_MTL,
dp.ETHERNET_DMA,
&mut DES_RING,
mac_addr.clone(),
)
};
unsafe {
ethernet::enable_interrupt();
cp.NVIC.set_priority(stm32::Interrupt::ETH, 196); // Mid prio
cortex_m::peripheral::NVIC::unmask(stm32::Interrupt::ETH);
}
let mut socket_set_entries: [_; 8] = Default::default(); // ----------------------------------------------------------
let mut sockets = net::socket::SocketSet::new(&mut socket_set_entries[..]); // Begin periodic tasks
add_socket!(sockets, rx_storage, tx_storage);
let tcp_stack = NetworkStack::new(&mut net_interface, sockets); systick_init(&mut delay.free(), ccdr.clocks);
let mut client = MqttClient::<consts::U256, _>::new( unsafe {
IpAddr::V4(Ipv4Addr::new(192, 168, 1, 125)), cp.SCB.shpr[15 - 4].write(128);
"nucleo", } // systick exception priority
tcp_stack,
) // ----------------------------------------------------------
.unwrap(); // Main application loop
// Setup addresses, maybe not MAC?
// MAC is set up in prior
let local_addr = IpAddress::v4(192, 168, 1, 200);
let mut ip_addrs = [IpCidr::new(local_addr, 24)];
// let neighbor_cache = NeighborCache::new(BTreeMap::new());
let mut neighbor_storage = [None; 16];
let neighbor_cache = NeighborCache::new(&mut neighbor_storage[..]);
// Routes
let default_v4_gw = Ipv4Address::new(192, 168, 1, 1);
let mut routes_storage = [None; 8];
let mut routes = Routes::new(&mut routes_storage[..]);
routes.add_default_ipv4_route(default_v4_gw).unwrap();
// Device? _eth_dma, as it implements phy::device
let mut iface = EthernetInterfaceBuilder::new(_eth_dma)
.ethernet_addr(mac_addr)
.neighbor_cache(neighbor_cache)
.ip_addrs(&mut ip_addrs[..])
.routes(routes)
.finalize();
// SCPI configs
// Device was declared in prior
// let mut errors = ArrayErrorQueue::<[Error; 10]>::new();
// let mut context = Context::new(&mut urukul, &mut errors, TREE);
// //Response bytebuffer
// let mut buf = ArrayVecFormatter::<[u8; 256]>::new();
// SCPI configs END
// TCP socket
let server_socket = {
static mut server_rx_storage :[u8; BUFFER_SIZE] = [0; BUFFER_SIZE];
static mut server_tx_storage :[u8; BUFFER_SIZE] = [0; BUFFER_SIZE];
let server_rx_buffer = TcpSocketBuffer::new( unsafe { &mut server_rx_storage[..] } );
let server_tx_buffer = TcpSocketBuffer::new( unsafe { &mut server_tx_storage[..] } );
TcpSocket::new(server_rx_buffer, server_tx_buffer)
};
// Setup a silent socket
let client_socket = {
static mut client_rx_storage :[u8; BUFFER_SIZE] = [0; BUFFER_SIZE];
static mut client_tx_storage :[u8; BUFFER_SIZE] = [0; BUFFER_SIZE];
let client_rx_buffer = TcpSocketBuffer::new( unsafe { &mut client_rx_storage[..] } );
let client_tx_buffer = TcpSocketBuffer::new( unsafe { &mut client_tx_storage[..] } );
TcpSocket::new(client_rx_buffer, client_tx_buffer)
};
// Socket storage
let mut sockets_storage: [_; 2] = Default::default();
let mut socket_set = SocketSet::new(&mut sockets_storage[..]);
let server_handle = socket_set.add(server_socket);
let client_handle = socket_set.add(client_socket);
loop { loop {
let tick = Instant::now() > next_ms; let _time = TIME.load(Ordering::Relaxed);
match iface.poll(&mut socket_set, Instant::from_millis(_time as i64)) {
Ok(_) => {
// hprintln!("Ethernet up").unwrap();
},
Err(e) => {
hprintln!("Ethernet down!").unwrap();
},
};
if tick { // Conenct to TCP server through port 49500
next_ms += 400_000.cycles(); {
time += 1; let mut socket = socket_set.get::<TcpSocket>(server_handle);
if !socket.is_active() && !socket.is_listening(){
socket.listen(7777).unwrap();
hprintln!("Server listening").unwrap();
}
// hprintln!("listener state :{}", socket.state()).unwrap();
if socket.can_recv() {
hprintln!("{:?}", str::from_utf8(socket.recv(|data| {
(data.len(), data)
}).unwrap()).unwrap()).unwrap();
}
} }
if tick && (time % 1000) == 0 { {
client let mut socket = socket_set.get::<TcpSocket>(client_handle);
.publish("nucleo", "Hello, World!".as_bytes(), QoS::AtMostOnce, &[]) if !socket.is_open() || !socket.can_send() {
.unwrap(); socket.abort();
socket.close();
// hprintln!("reset state: {}", socket.state()).unwrap();
socket.connect((IpAddress::v4(192, 168, 1, 200), 1883),
(IpAddress::Unspecified, 45000)).unwrap();
// hprintln!("post connect state: {}", socket.state()).unwrap();
}
// hprintln!("client state: {}", socket.state()).unwrap();
if socket.can_send() {
socket.send_slice(b"regards from socket").unwrap();
}
} }
client
.poll(|_client, topic, message, _properties| match topic {
_ => hprintln!("On '{:?}', received: {:?}", topic, message).unwrap(),
})
.unwrap();
// Update the TCP stack.
let sleep = client.network_stack.update(time);
if sleep {
//cortex_m::asm::wfi();
cortex_m::asm::nop();
}
match client.is_connected() {
true => hprintln!("Connected"),
false => hprintln!("No Connection"),
}.unwrap();
} }
} }
use stm32h7xx_hal::gpio::{
gpioa::{PA1, PA2, PA7},
gpiob::{PB13},
gpioc::{PC1, PC4, PC5},
gpiog::{PG11, PG13},
Speed::VeryHigh,
};
/*
* Migrated ethernet setup pins
*/
pub fn setup_ethernet_pins<REF_CLK, MDIO, MDC, CRS_DV, RXD0, RXD1, TX_EN, TXD0, TXD1>(
pa1: PA1<REF_CLK>, pa2: PA2<MDIO>, pc1: PC1<MDC>, pa7: PA7<CRS_DV>, pc4: PC4<RXD0>,
pc5: PC5<RXD1>, pg11: PG11<TX_EN>, pg13: PG13<TXD0>, pb13: PB13<TXD1>
) {
pa1.into_alternate_af11().set_speed(VeryHigh);
pa2.into_alternate_af11().set_speed(VeryHigh);
pc1.into_alternate_af11().set_speed(VeryHigh);
pa7.into_alternate_af11().set_speed(VeryHigh);
pc4.into_alternate_af11().set_speed(VeryHigh);
pc5.into_alternate_af11().set_speed(VeryHigh);
pg11.into_alternate_af11().set_speed(VeryHigh);
pg13.into_alternate_af11().set_speed(VeryHigh);
pb13.into_alternate_af11().set_speed(VeryHigh);
}
#[interrupt]
fn ETH() {
unsafe { ethernet::interrupt_handler() }
}
#[exception]
fn SysTick() {
TIME.fetch_add(1, Ordering::Relaxed);
}
#[exception]
fn HardFault(ef: &cortex_m_rt::ExceptionFrame) -> ! {
panic!("HardFault at {:#?}", ef);
}
#[exception]
fn DefaultHandler(irqn: i16) {
panic!("Unhandled exception (IRQn = {})", irqn);
}