diff --git a/ports/nrf/boards/challenger_840/board.c b/ports/nrf/boards/challenger_840/board.c
index fb1ce4fb83..677b6eac8b 100644
--- a/ports/nrf/boards/challenger_840/board.c
+++ b/ports/nrf/boards/challenger_840/board.c
@@ -25,5 +25,12 @@
  */
 
 #include "supervisor/board.h"
+#include "nrf_gpio.h"
+
+#define PORTPIN(x, y)     (x * 32 + y)
 
 // Use the MP_WEAK supervisor/shared/board.c versions of routines not defined here.
+void board_init(void) {
+  nrf_gpio_cfg_output(PORTPIN(1, 9));
+  nrf_gpio_pin_write(PORTPIN(1, 9), 1);
+}
diff --git a/ports/nrf/boards/challenger_840/pins.c b/ports/nrf/boards/challenger_840/pins.c
index 26d780fffe..e059c17a15 100644
--- a/ports/nrf/boards/challenger_840/pins.c
+++ b/ports/nrf/boards/challenger_840/pins.c
@@ -32,6 +32,7 @@ STATIC const mp_rom_map_elem_t board_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR_D13), MP_ROM_PTR(&pin_P0_06) },
 
     { MP_ROM_QSTR(MP_QSTR_NEOPIXEL), MP_ROM_PTR(&pin_P1_08) },
+    { MP_ROM_QSTR(MP_QSTR_LDO_CONTROL), MP_ROM_PTR(&pin_P1_09) },
 
     { MP_ROM_QSTR(MP_QSTR_SCL), MP_ROM_PTR(&pin_P0_12) },
     { MP_ROM_QSTR(MP_QSTR_SDA), MP_ROM_PTR(&pin_P0_11) },