diff --git a/cc3200/mods/modusocket.c b/cc3200/mods/modusocket.c
index 35964fa053..56e0946a7f 100644
--- a/cc3200/mods/modusocket.c
+++ b/cc3200/mods/modusocket.c
@@ -276,7 +276,7 @@ STATIC int wlan_socket_ioctl (mod_network_socket_obj_t *s, mp_uint_t request, mp
             ret |= MP_STREAM_POLL_HUP;
         }
     } else {
-        *_errno = EINVAL;
+        *_errno = MP_EINVAL;
         ret = MP_STREAM_ERROR;
     }
     return ret;
@@ -519,7 +519,7 @@ STATIC mp_obj_t socket_recv(mp_obj_t self_in, mp_obj_t len_in) {
     int _errno;
     mp_int_t ret = wlan_socket_recv(self, (byte*)vstr.buf, len, &_errno);
     if (ret < 0) {
-        if (_errno == EAGAIN && self->sock_base.has_timeout) {
+        if (_errno == MP_EAGAIN && self->sock_base.has_timeout) {
             mp_raise_msg(&mp_type_TimeoutError, "timed out");
         }
         mp_raise_OSError(-_errno);
@@ -565,7 +565,7 @@ STATIC mp_obj_t socket_recvfrom(mp_obj_t self_in, mp_obj_t len_in) {
     int _errno;
     mp_int_t ret = wlan_socket_recvfrom(self, (byte*)vstr.buf, vstr.len, ip, &port, &_errno);
     if (ret < 0) {
-        if (_errno == EAGAIN && self->sock_base.has_timeout) {
+        if (_errno == MP_EAGAIN && self->sock_base.has_timeout) {
             mp_raise_msg(&mp_type_TimeoutError, "timed out");
         }
         mp_raise_OSError(-_errno);
diff --git a/cc3200/mods/pybuart.c b/cc3200/mods/pybuart.c
index dceb842d52..f28af9063a 100644
--- a/cc3200/mods/pybuart.c
+++ b/cc3200/mods/pybuart.c
@@ -596,8 +596,8 @@ STATIC mp_uint_t pyb_uart_read(mp_obj_t self_in, void *buf_in, mp_uint_t size, i
 
     // wait for first char to become available
     if (!uart_rx_wait(self)) {
-        // return EAGAIN error to indicate non-blocking (then read() method returns None)
-        *errcode = EAGAIN;
+        // return MP_EAGAIN error to indicate non-blocking (then read() method returns None)
+        *errcode = MP_EAGAIN;
         return MP_STREAM_ERROR;
     }
 
@@ -639,7 +639,7 @@ STATIC mp_uint_t pyb_uart_ioctl(mp_obj_t self_in, mp_uint_t request, mp_uint_t a
             ret |= MP_STREAM_POLL_WR;
         }
     } else {
-        *errcode = EINVAL;
+        *errcode = MP_EINVAL;
         ret = MP_STREAM_ERROR;
     }
     return ret;
diff --git a/cc3200/mpconfigport.h b/cc3200/mpconfigport.h
index 944a6c0716..91d14dd1e3 100644
--- a/cc3200/mpconfigport.h
+++ b/cc3200/mpconfigport.h
@@ -75,6 +75,7 @@
 #define MICROPY_STREAMS_NON_BLOCK                   (1)
 #define MICROPY_MODULE_WEAK_LINKS                   (1)
 #define MICROPY_CAN_OVERRIDE_BUILTINS               (1)
+#define MICROPY_USE_INTERNAL_ERRNO                  (1)
 #define MICROPY_VFS                                 (1)
 #define MICROPY_VFS_FAT                             (1)
 #define MICROPY_PY_ASYNC_AWAIT (0)