From 4b63a8c9b4c2aca87da19bab45e7bebe3368d36c Mon Sep 17 00:00:00 2001
From: Jeff Epler <jepler@gmail.com>
Date: Thu, 25 Feb 2021 11:34:03 -0600
Subject: [PATCH] rp2pio: allow keyboard interrupt while waiting for tx fifo to
 empty (& stall)

---
 ports/raspberrypi/common-hal/rp2pio/StateMachine.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/ports/raspberrypi/common-hal/rp2pio/StateMachine.c b/ports/raspberrypi/common-hal/rp2pio/StateMachine.c
index 5625a1b29c..54c5220e70 100644
--- a/ports/raspberrypi/common-hal/rp2pio/StateMachine.c
+++ b/ports/raspberrypi/common-hal/rp2pio/StateMachine.c
@@ -673,6 +673,9 @@ static bool _transfer(rp2pio_statemachine_obj_t *self,
         while (!pio_sm_is_tx_fifo_empty(self->pio, self->state_machine) ||
                (self->wait_for_txstall && (self->pio->fdebug & stall_mask) == 0)) {
             RUN_BACKGROUND_TASKS;
+            if (mp_hal_is_interrupted()) {
+                break;
+            }
         }
     }
     return true;