Tx only does not work

dma_gpio2/src/config.rs

@@ -0,0 +1,16 @@
+// src/config.rs
+use crate::software_uart::uart_emulation::{Parity, StopBits, UartConfig};
+
+pub const BAUD: u32 = 9_600;
+pub const TX_PIN_BIT: u8 = 2; // PA2
+pub const TX_OVERSAMPLE: u16 = 1;
+pub const RX_OVERSAMPLE: u16 = 16;
+pub const RX_RING_BYTES: usize = 4096;
+pub const TX_RING_BYTES: usize = 4096;
+pub const PIPE_RX_SIZE: usize = 256;
+
+pub const UART_CFG: UartConfig = UartConfig {
+    data_bits: 8,
+    parity: Parity::None,
+    stop_bits: StopBits::One,
+};