diff --git a/Makefile b/Makefile
index 751305f2..19300983 100644
--- a/Makefile
+++ b/Makefile
@@ -39,7 +39,7 @@ FW_BASE		= firmware
 XTENSA_TOOLS_ROOT ?= $(abspath ../esp-open-sdk/xtensa-lx106-elf/bin)/
 
 # Base directory of the ESP8266 SDK package, absolute
-SDK_BASE	?= $(abspath ../esp_iot_sdk_v1.0.1)
+SDK_BASE	?= $(abspath ../esp_iot_sdk_v1.1.0)
 
 #Esptool.py path and port
 ESPTOOL		?= esptool.py
diff --git a/include/espmissingincludes.h b/include/espmissingincludes.h
index 8c1334e3..77fc7e0a 100644
--- a/include/espmissingincludes.h
+++ b/include/espmissingincludes.h
@@ -10,10 +10,12 @@
 typedef struct espconn espconn;
 
 int atoi(const char *nptr);
-void ets_install_putc1(void *routine);
+
+void ets_install_putc1(void *routine); // necessary for #define os_xxx -> ets_xxx
 void ets_isr_attach(int intr, void *handler, void *arg);
 void ets_isr_mask(unsigned intr);
 void ets_isr_unmask(unsigned intr);
+
 int ets_memcmp(const void *s1, const void *s2, size_t n);
 void *ets_memcpy(void *dest, const void *src, size_t n);
 void *ets_memset(void *s, int c, size_t n);
@@ -25,23 +27,41 @@ size_t ets_strlen(const char *s);
 int ets_strncmp(const char *s1, const char *s2, int len);
 char *ets_strncpy(char *dest, const char *src, size_t n);
 char *ets_strstr(const char *haystack, const char *needle);
+
 void ets_timer_arm_new(ETSTimer *a, int b, int c, int isMstimer);
 void ets_timer_disarm(ETSTimer *a);
 void ets_timer_setfn(ETSTimer *t, ETSTimerFunc *fn, void *parg);
+
 void ets_update_cpu_frequency(int freqmhz);
+
 int os_printf(const char *format, ...)  __attribute__ ((format (printf, 1, 2)));
 int os_snprintf(char *str, size_t size, const char *format, ...) __attribute__ ((format (printf, 3, 4)));
 int os_printf_plus(const char *format, ...)  __attribute__ ((format (printf, 1, 2)));
+
 void pvPortFree(void *ptr);
 void *pvPortMalloc(size_t xWantedSize);
 void *pvPortZalloc(size_t);
 void uart_div_modify(int no, unsigned int freq);
 void vPortFree(void *ptr);
 void *vPortMalloc(size_t xWantedSize);
-uint8 wifi_get_opmode(void);
 uint32 system_get_time();
-int os_random();
+//uint8 wifi_get_opmode(void); // defined in SDK 1.0.0 onwards
+//int os_random(); // defined in SDK 1.1.0 onwards
 int rand(void);
 void ets_bzero(void *s, size_t n);
 void ets_delay_us(int ms);
+
+// disappeared in SDK 1.1.0:
+#define os_timer_done ets_timer_done
+#define os_timer_handler_isr ets_timer_handler_isr
+#define os_timer_init ets_timer_init
+
+// This is not missing in SDK 1.1.0 but causes a parens error
+#undef PIN_FUNC_SELECT
+#define PIN_FUNC_SELECT(PIN_NAME, FUNC)  do { \
+    WRITE_PERI_REG(PIN_NAME,   \
+        (READ_PERI_REG(PIN_NAME) & ~(PERIPHS_IO_MUX_FUNC<<PERIPHS_IO_MUX_FUNC_S))  \
+            |( (((FUNC&BIT2)<<2)|(FUNC&0x3))<<PERIPHS_IO_MUX_FUNC_S) );  \
+    } while (0)
+
 #endif
diff --git a/serial/uart.c b/serial/uart.c
index 1fd96fe5..1ec63cff 100644
--- a/serial/uart.c
+++ b/serial/uart.c
@@ -47,16 +47,16 @@ uart_config(uint8 uart_no)
 {
   if (uart_no == UART1) {
     PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO2_U, FUNC_U1TXD_BK);
-		PIN_PULLDWN_DIS(PERIPHS_IO_MUX_GPIO2_U);
+		//PIN_PULLDWN_DIS(PERIPHS_IO_MUX_GPIO2_U);
 		PIN_PULLUP_DIS(PERIPHS_IO_MUX_GPIO2_U);
   } else {
     /* rcv_buff size is 0x100 */
     ETS_UART_INTR_ATTACH(uart0_rx_intr_handler,  &(UartDev.rcv_buff));
     PIN_PULLUP_DIS (PERIPHS_IO_MUX_U0TXD_U);
-    PIN_PULLDWN_DIS(PERIPHS_IO_MUX_U0TXD_U);
+    //PIN_PULLDWN_DIS(PERIPHS_IO_MUX_U0TXD_U);
     PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0TXD_U, FUNC_U0TXD);
     PIN_PULLUP_DIS (PERIPHS_IO_MUX_U0RXD_U);
-    PIN_PULLDWN_DIS(PERIPHS_IO_MUX_U0RXD_U);
+    //PIN_PULLDWN_DIS(PERIPHS_IO_MUX_U0RXD_U);
     PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0RXD_U, 0); // FUNC_U0RXD==0
   }
 
diff --git a/user/user_main.c b/user/user_main.c
index 1d1540dd..c3faab88 100644
--- a/user/user_main.c
+++ b/user/user_main.c
@@ -95,6 +95,9 @@ static void ICACHE_FLASH_ATTR prHeapTimerCb(void *arg) {
 }
 #endif
 
+void user_rf_pre_init(void) {
+}
+
 // address of espfs binary blob
 extern uint32_t _binary_espfs_img_start;