diff --git a/cc3200/mods/modmachine.c b/cc3200/mods/modmachine.c
index 704defb33724a0f1e3fdbd03ed3dfe6912bc217c..410d5b944c0a36c7663d50db1bd8cdf7263bec9d 100644
--- a/cc3200/mods/modmachine.c
+++ b/cc3200/mods/modmachine.c
@@ -198,7 +198,8 @@ STATIC const mp_map_elem_t machine_module_globals_table[] = {
     { MP_OBJ_NEW_QSTR(MP_QSTR_IDLE),                MP_OBJ_NEW_SMALL_INT(PYB_PWR_MODE_ACTIVE) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_SLEEP),               MP_OBJ_NEW_SMALL_INT(PYB_PWR_MODE_LPDS) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_DEEPSLEEP),           MP_OBJ_NEW_SMALL_INT(PYB_PWR_MODE_HIBERNATE) },
-    { MP_OBJ_NEW_QSTR(MP_QSTR_POWER_ON),            MP_OBJ_NEW_SMALL_INT(PYB_SLP_PWRON_RESET) },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_POWER_ON),            MP_OBJ_NEW_SMALL_INT(PYB_SLP_PWRON_RESET) }, // legacy constant
+    { MP_OBJ_NEW_QSTR(MP_QSTR_PWRON_RESET),         MP_OBJ_NEW_SMALL_INT(PYB_SLP_PWRON_RESET) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_HARD_RESET),          MP_OBJ_NEW_SMALL_INT(PYB_SLP_HARD_RESET) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_WDT_RESET),           MP_OBJ_NEW_SMALL_INT(PYB_SLP_WDT_RESET) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_DEEPSLEEP_RESET),     MP_OBJ_NEW_SMALL_INT(PYB_SLP_HIB_RESET) },
diff --git a/docs/library/machine.rst b/docs/library/machine.rst
index 0f361a7cb7cfbd02700463172a3f420004a77e9e..46d8eea71f1c7b974c18b3725aeb6278c8e54e55 100644
--- a/docs/library/machine.rst
+++ b/docs/library/machine.rst
@@ -125,7 +125,7 @@ Constants
 
     irq wake values
 
-.. data:: machine.POWER_ON
+.. data:: machine.PWRON_RESET
 .. data:: machine.HARD_RESET
 .. data:: machine.WDT_RESET
 .. data:: machine.DEEPSLEEP_RESET
diff --git a/esp8266/modmachine.c b/esp8266/modmachine.c
index a8d2de8bb8b434031f62600b8e1769954b5dff7a..b0b7f3a1a3a740aae4aa602c6f1055e4b538ef17 100644
--- a/esp8266/modmachine.c
+++ b/esp8266/modmachine.c
@@ -260,7 +260,7 @@ STATIC const mp_rom_map_elem_t machine_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR_DEEPSLEEP), MP_ROM_INT(MACHINE_WAKE_DEEPSLEEP) },
 
     // reset causes
-    { MP_ROM_QSTR(MP_QSTR_PWR_ON_RESET), MP_ROM_INT(REASON_DEFAULT_RST) },
+    { MP_ROM_QSTR(MP_QSTR_PWRON_RESET), MP_ROM_INT(REASON_DEFAULT_RST) },
     { MP_ROM_QSTR(MP_QSTR_HARD_RESET), MP_ROM_INT(REASON_EXT_SYS_RST) },
     { MP_ROM_QSTR(MP_QSTR_DEEPSLEEP_RESET), MP_ROM_INT(REASON_DEEP_SLEEP_AWAKE) },
     { MP_ROM_QSTR(MP_QSTR_WDT_RESET), MP_ROM_INT(REASON_WDT_RST) },
diff --git a/stmhal/modmachine.c b/stmhal/modmachine.c
index dbeabec55b65661a72b7378dda22c672a40d6929..ca17eff8076225cbfeb20ede6b9abc537c1ea00a 100644
--- a/stmhal/modmachine.c
+++ b/stmhal/modmachine.c
@@ -543,7 +543,7 @@ STATIC const mp_map_elem_t machine_module_globals_table[] = {
     { MP_OBJ_NEW_QSTR(MP_QSTR_SLEEP),               MP_OBJ_NEW_SMALL_INT(PYB_PWR_MODE_LPDS) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_DEEPSLEEP),           MP_OBJ_NEW_SMALL_INT(PYB_PWR_MODE_HIBERNATE) },
 #endif
-    { MP_OBJ_NEW_QSTR(MP_QSTR_POWER_ON),            MP_OBJ_NEW_SMALL_INT(PYB_RESET_POWER_ON) },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_PWRON_RESET),         MP_OBJ_NEW_SMALL_INT(PYB_RESET_POWER_ON) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_HARD_RESET),          MP_OBJ_NEW_SMALL_INT(PYB_RESET_HARD) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_WDT_RESET),           MP_OBJ_NEW_SMALL_INT(PYB_RESET_WDT) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_DEEPSLEEP_RESET),     MP_OBJ_NEW_SMALL_INT(PYB_RESET_DEEPSLEEP) },