From b460d6dc4706b9ade1c2f5bb06d3fdb07c07c343 Mon Sep 17 00:00:00 2001
From: Laurens Valk <laurens@pybricks.com>
Date: Tue, 1 Oct 2024 16:38:04 +0200
Subject: [PATCH] bricks/_common_stm32: Run pool hook on print if disconnected.

Fixes certain tight loops with f-strings locking up the hub when disconnected.

Fixes https://github.com/pybricks/support/issues/1668
---
 CHANGELOG.md                     | 2 ++
 bricks/_common_stm32/mphalport.c | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3d4df1227..ead41ae2a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,8 +14,10 @@
   from `3.6.0b1` to `3.5.0` and back to `3.6.0b1` ([support#1846]).
 - Fixed controls stopping if `use_gyro` is called again with the same
   argument as already active ([support#1858]).
+- Fixed lockup and reboot with f-strings in tight loops ([support#1668]).
 
 [support#1623]: https://github.com/pybricks/support/issues/1623
+[support#1668]: https://github.com/pybricks/support/issues/1668
 [support#1846]: https://github.com/pybricks/support/issues/1846
 [support#1858]: https://github.com/pybricks/support/issues/1858
 
diff --git a/bricks/_common_stm32/mphalport.c b/bricks/_common_stm32/mphalport.c
index d2a2fc30c..19356583d 100644
--- a/bricks/_common_stm32/mphalport.c
+++ b/bricks/_common_stm32/mphalport.c
@@ -138,13 +138,13 @@ void mp_hal_stdout_tx_strn(const char *str, mp_uint_t len) {
             continue;
         }
 
+        MICROPY_EVENT_POLL_HOOK
+
         if (err != PBIO_ERROR_AGAIN) {
             // Ignoring error for now. This means stdout lost if Bluetooth is
             // disconnected.
             return;
         }
-
-        MICROPY_EVENT_POLL_HOOK
     }
 }