diff --git a/firmware/rust1/src/rs485.rs b/firmware/rust1/src/rs485.rs
index 5561c8ec57fc93dde6e636d0cc7dec8f42a0a664..e3cf3dd9e3e979dd53038cd141dfb2b78a1be7b4 100644
--- a/firmware/rust1/src/rs485.rs
+++ b/firmware/rust1/src/rs485.rs
@@ -266,7 +266,9 @@ impl<H: RS485Handler> RS485<H> {
         sm1.set_pin_dirs(embassy_rp::pio::Direction::Out, &[&tx_en_pin_pio, &tx_pin_pio]);
         sm1.set_enable(true);
 
-        const TX_BUF_LENGTH: usize = 32; //H::TX_BUF_LENGTH;
+        //FIXME Do we have any way to get this number from the outside?
+        const TX_BUF_LENGTH: usize = 256;
+        defmt::assert!(TX_BUF_LENGTH == H::TX_BUF_LENGTH);
         let mut tx_data = [0u32; TX_BUF_LENGTH+1];
         let mut tx_in_progress = false;