Minor SPI refactors (#90)

* chore: SPI make method names consistent, remove obsolete commentary
* test(spim0): print on uDMA UART instead of APB UART 0

examples/headsail-bsp/src/sysctrl/udma/spim.rs

@@ -57,14 +57,12 @@ impl<'u> UdmaSpim<'u, Enabled> {
             .write(|w| unsafe { w.bits(buf.len() as u32) });
 
         // Dispatch transmission
-        spim.spim_tx_cfg().write(
-            |w| w.en().set_bit(), // If we want "continuous mode". In continuous mode, uDMA reloads the address and transmits it again
-                                  //.continous().set_bit()
-        );
+        spim.spim_tx_cfg().write(|w| w.en().set_bit());
 
         // Poll until finished (prevents `buf` leakage)
         while spim.spim_tx_saddr().read().bits() != 0 {}
     }
+
     pub fn write_rx(&mut self, buf: &[u8]) {
         let spim = &self.0;
 
@@ -75,10 +73,7 @@ impl<'u> UdmaSpim<'u, Enabled> {
             .write(|w| unsafe { w.bits(buf.len() as u32) });
 
         // Dispatch transmission
-        spim.spim_rx_cfg().write(
-            |w| w.en().set_bit(), // If we want "continuous mode". In continuous mode, uDMA reloads the address and transmits it again
-                                  //.continous().set_bit()
-        );
+        spim.spim_rx_cfg().write(|w| w.en().set_bit());
 
         // Poll until finished (prevents `buf` leakage)
         while spim.spim_rx_saddr().read().bits() != 0 {}
@@ -178,7 +173,7 @@ impl<'u> UdmaSpim<'u, Enabled> {
     ///   spim.eot();
     ///
     /// ```
-    pub fn receive(&mut self, data: &[u8]) {
+    pub fn receive_data(&mut self, data: &[u8]) {
         let mut cmd_data: [u8; 12] = [0; 12];
 
         cmd_data[0..4].copy_from_slice(

examples/sysctrl/hello-sysctrl/examples/spim0.rs

@@ -7,22 +7,29 @@
 #![no_main]
 
 use core::arch::asm;
-use headsail_bsp::apb_uart::ApbUart0;
-use headsail_bsp::{pac::Sysctrl, rt::entry, sysctrl::udma::Udma};
+use headsail_bsp::{
+    pac::Sysctrl,
+    rt::entry,
+    sysctrl::{soc_ctrl, udma::Udma},
+    ufmt,
+};
+use hello_sysctrl::{print_example_name, sprintln};
 
 #[entry]
 fn main() -> ! {
+    // These lines are necessary to initialize uDMA UART prints for sprint-macro
+    soc_ctrl::periph_clk_div_set(0);
+    hello_sysctrl::UdmaUart::init();
+    print_example_name!();
+
     let sysctrl = unsafe { Sysctrl::steal() };
     let udma = Udma(sysctrl.udma());
 
     // Split uDMA into sub-drivers for each peripheral
     let udma_periphs = udma.split();
 
-    let (soc_freq, baud) = (30_000_000, 115_200);
-    let mut uart = ApbUart0::init(soc_freq, baud);
-
     let mut spim = udma_periphs.spim.enable();
-    uart.write_str("SPI enabled!\n\r");
+    sprintln!("SPI enabled!");
 
     let tx_data: [u8; 8] = [0x01, 0x42, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08];
     let rx_data: [u8; 8] = [0; 8];
@@ -32,16 +39,16 @@ fn main() -> ! {
     // Send 8 bytes
     spim.send_data(&tx_data);
     spim.write_eot_keep_cs();
-    uart.write_str("Data sent!\n\r");
+    sprintln!("Data sent!\n\r");
 
     for _ in 0..10_000 {
         unsafe { asm!("nop") }
     }
 
     // Receive 8 bytes
-    spim.receive(&rx_data);
+    spim.receive_data(&rx_data);
     spim.write_eot();
-    uart.write_str("Data received!\n\r");
+    sprintln!("Data received!\n\r");
 
     loop {
         continue;