diff --git a/artiq/firmware/runtime/main.rs b/artiq/firmware/runtime/main.rs
index fda9d37ba..73660b611 100644
--- a/artiq/firmware/runtime/main.rs
+++ b/artiq/firmware/runtime/main.rs
@@ -107,6 +107,9 @@ fn startup() {
         io_expander1 = board_misoc::io_expander::IoExpander::new(1);
         io_expander0.init().expect("I2C I/O expander #0 initialization failed");
         io_expander1.init().expect("I2C I/O expander #1 initialization failed");
+        io_expander0.set_oe(0, 1 << 1).unwrap();
+        io_expander0.set(0, 1, false);
+        io_expander0.service().unwrap();
     }
     rtio_clocking::init();
 
diff --git a/artiq/firmware/satman/main.rs b/artiq/firmware/satman/main.rs
index 9e2144370..60f0f4c0a 100644
--- a/artiq/firmware/satman/main.rs
+++ b/artiq/firmware/satman/main.rs
@@ -475,6 +475,9 @@ pub extern fn main() -> i32 {
             io_expander1.set(1, 7, true);
             io_expander1.service().unwrap();
         }
+        io_expander0.set_oe(0, 1 << 1).unwrap();
+        io_expander0.set(0, 1, false);
+        io_expander0.service().unwrap();
     }
 
     #[cfg(has_si5324)]