solution detached from main for async buffered generalized2

dma_gpio/src/bin/main.rs

@@ -25,7 +25,7 @@ static PIPE: Pipe<CriticalSectionRawMutex, 256> = Pipe::new();
 // Baud rate: one TIM6 update equals one UART bit-time
 const BAUD: u32 = 115_200;
 const TX_PIN_BIT: u8 = 2; // PA2
-const OVERSAMPLE: u16 = 6;
+const OVERSAMPLE: u16 = 16;
 
 const UART_CFG: UartConfig = UartConfig {
     data_bits: 8,
@@ -125,7 +125,7 @@ async fn dma_tx_task(ch: Peri<'static, GPDMA1_CH0>) {
         {
             Ok(()) => {}
             Err(_) => {
-                warn!("DMA timeout: no TIM6 request (wrong DMAMUX req?)");
+                warn!("DMA timeout: no TIM6 request");
                 dump_tim6_regs();
                 dump_dma_ch0_regs();
             }

dma_gpio/src/dma_timer.rs

@@ -28,7 +28,7 @@ pub fn init_tim6_for_uart<'d>(tim6: Peri<'d, TIM6>, baud: u32, oversample: u16)
     ll.regs_basic().cr1().write(|w| {
         w.set_cen(false);
         w.set_opm(false);
-        w.set_udis(false);          // boolean field: false = allow UEV
+        w.set_udis(false);           // boolean field: false = allow UEV
         w.set_urs(Urs::ANY_EVENT);   // enum field: DMA+interrupts on any event
     });
 
@@ -47,5 +47,5 @@ pub fn init_tim6_for_uart<'d>(tim6: Peri<'d, TIM6>, baud: u32, oversample: u16)
         w.set_udis(false);
         w.set_urs(Urs::ANY_EVENT);
     });
-    mem::forget(ll);
+    mem::forget(ll); // KEEP THE TIMER ALIVE
 }