diff --git a/esp-link/cgiflash.c b/esp-link/cgiflash.c
index 1ce8469..0fe3feb 100644
--- a/esp-link/cgiflash.c
+++ b/esp-link/cgiflash.c
@@ -179,7 +179,7 @@ int ICACHE_FLASH_ATTR cgiRebootFirmware(HttpdConnData *connData) {
   system_upgrade_flag_set(UPGRADE_FLAG_FINISH);
   os_timer_disarm(&flash_reboot_timer);
   os_timer_setfn(&flash_reboot_timer, (os_timer_func_t *)system_upgrade_reboot, NULL);
-  os_timer_arm_us(&flash_reboot_timer, 2 * 1000000, 1);
+  os_timer_arm(&flash_reboot_timer, 2000, 1);
   return HTTPD_CGI_DONE;
 }
 
@@ -193,6 +193,6 @@ int ICACHE_FLASH_ATTR cgiReset(HttpdConnData *connData) {
   // Schedule a reboot
   os_timer_disarm(&flash_reboot_timer);
   os_timer_setfn(&flash_reboot_timer, (os_timer_func_t *)system_restart, NULL);
-  os_timer_arm_us(&flash_reboot_timer, 2 * 1000000, 1);
+  os_timer_arm(&flash_reboot_timer, 2000, 1);
   return HTTPD_CGI_DONE;
 }
diff --git a/esp-link/cgimega.c b/esp-link/cgimega.c
index d5acec0..38fce83 100644
--- a/esp-link/cgimega.c
+++ b/esp-link/cgimega.c
@@ -25,7 +25,7 @@
  *     The number of data bytes in the record must match the number specified by the ll field.
  *   cc is the checksum field that represents the checksum of the record. The checksum is
  *     calculated by summing the values of all hexadecimal digit pairs in the record modulo
- *     256 and taking the two's complement. 
+ *     256 and taking the two's complement.
  *
  */
 
@@ -211,7 +211,7 @@ int ICACHE_FLASH_ATTR cgiMegaSync(HttpdConnData *connData) {
 	allocateOptibootData();
       DBG("OB got sync\n");
       os_sprintf(buf, "SYNC at %d baud, board %02x.%02x.%02x, hardware v%d, firmware %d.%d",
-	baudRate, optibootData->signature[0], optibootData->signature[1], optibootData->signature[2], 
+	baudRate, optibootData->signature[0], optibootData->signature[1], optibootData->signature[2],
 	optibootData->hardwareVersion, optibootData->firmwareVersionMajor, optibootData->firmwareVersionMinor);
       httpdSend(connData, buf, -1);
     } else if (errMessage[0] && progState == stateSync) {
@@ -375,7 +375,7 @@ static int ICACHE_FLASH_ATTR readPacket() {
   }
 
   return len;
-} 
+}
 
 static int ICACHE_FLASH_ATTR readSyncPacket() {
   int len = readPacket();
diff --git a/esp-link/cgioptiboot.c b/esp-link/cgioptiboot.c
index c94ac96..c3ca1ea 100644
--- a/esp-link/cgioptiboot.c
+++ b/esp-link/cgioptiboot.c
@@ -128,7 +128,7 @@ int ICACHE_FLASH_ATTR cgiOptibootSync(HttpdConnData *connData) {
     // start sync timer
     os_timer_disarm(&optibootTimer);
     os_timer_setfn(&optibootTimer, optibootTimerCB, NULL);
-    os_timer_arm_us(&optibootTimer, INIT_DELAY * 1000, 0);
+    os_timer_arm(&optibootTimer, INIT_DELAY, 0);
 
     // respond with optimistic OK
     noCacheHeaders(connData, 204);
@@ -382,7 +382,7 @@ bool ICACHE_FLASH_ATTR optibootProgramPage(void) {
 
 static void ICACHE_FLASH_ATTR armTimer(uint32_t ms) {
   os_timer_disarm(&optibootTimer);
-  os_timer_arm_us(&optibootTimer, ms * 1000, 0);
+  os_timer_arm(&optibootTimer, ms, 0);
 }
 
 static int baudRates[] = { 0, 9600, 57600, 115200 };
diff --git a/esp-link/cgipins.c b/esp-link/cgipins.c
index bf4754d..b763d12 100644
--- a/esp-link/cgipins.c
+++ b/esp-link/cgipins.c
@@ -32,10 +32,9 @@ int ICACHE_FLASH_ATTR cgiPinsGet(HttpdConnData *connData) {
   int len;
 
   len = os_sprintf(buff,
-      "{ \"reset\":%d, \"isp\":%d, \"conn\":%d, \"ser\":%d, \"swap\":%d, \"rxpup\":%d, \"txen\":%d }",
+      "{ \"reset\":%d, \"isp\":%d, \"conn\":%d, \"ser\":%d, \"swap\":%d, \"rxpup\":%d }",
       flashConfig.reset_pin, flashConfig.isp_pin, flashConfig.conn_led_pin,
-      flashConfig.ser_led_pin, !!flashConfig.swap_uart, !!flashConfig.rx_pullup,
-      flashConfig.tx_enable_pin);
+      flashConfig.ser_led_pin, !!flashConfig.swap_uart, !!flashConfig.rx_pullup);
 
   jsonHeader(connData, 200);
   httpdSend(connData, buff, len);
@@ -49,7 +48,7 @@ int ICACHE_FLASH_ATTR cgiPinsSet(HttpdConnData *connData) {
   }
 
   int8_t ok = 0;
-  int8_t reset, isp, conn, ser, tx_enable;
+  int8_t reset, isp, conn, ser;
   uint8_t swap, rxpup;
   ok |= getInt8Arg(connData, "reset", &reset);
   ok |= getInt8Arg(connData, "isp", &isp);
@@ -57,7 +56,6 @@ int ICACHE_FLASH_ATTR cgiPinsSet(HttpdConnData *connData) {
   ok |= getInt8Arg(connData, "ser", &ser);
   ok |= getBoolArg(connData, "swap", &swap);
   ok |= getBoolArg(connData, "rxpup", &rxpup);
-  ok |= getInt8Arg(connData, "txen", &tx_enable);
   if (ok < 0) return HTTPD_CGI_DONE;
 
   char *coll;
@@ -77,10 +75,6 @@ int ICACHE_FLASH_ATTR cgiPinsSet(HttpdConnData *connData) {
       if (pins & (1<<ser)) { coll = "Serial LED"; goto collision; }
       pins |= 1 << ser;
     }
-    if (tx_enable >= 0) {
-        if (pins & (1<<tx_enable)) { coll = "TX Enable"; goto collision; }
-        pins |= 1 << tx_enable;
-    }
     if (swap) {
       if (pins & (1<<15)) { coll = "Uart TX"; goto collision; }
       if (pins & (1<<13)) { coll = "Uart RX"; goto collision; }
@@ -96,9 +90,8 @@ int ICACHE_FLASH_ATTR cgiPinsSet(HttpdConnData *connData) {
     flashConfig.ser_led_pin = ser;
     flashConfig.swap_uart = swap;
     flashConfig.rx_pullup = rxpup;
-    flashConfig.tx_enable_pin = tx_enable;
-    os_printf("Pins changed: reset=%d isp=%d conn=%d ser=%d swap=%d rx-pup=%d tx_enable=%d\n",
-	reset, isp, conn, ser, swap, rxpup, tx_enable);
+    os_printf("Pins changed: reset=%d isp=%d conn=%d ser=%d swap=%d rx-pup=%d\n",
+	reset, isp, conn, ser, swap, rxpup);
 
     // apply the changes
     serbridgeInitPins();
diff --git a/esp-link/cgiservices.c b/esp-link/cgiservices.c
index eb35661..dddb616 100644
--- a/esp-link/cgiservices.c
+++ b/esp-link/cgiservices.c
@@ -39,7 +39,7 @@ int ICACHE_FLASH_ATTR cgiSystemSet(HttpdConnData *connData) {
     // schedule hostname change-over
     os_timer_disarm(&reassTimer);
     os_timer_setfn(&reassTimer, configWifiIP, NULL);
-    os_timer_arm_us(&reassTimer, 1 * 1000000, 0); // 1 second for the response of this request to make it
+    os_timer_arm(&reassTimer, 1000, 0); // 1 second for the response of this request to make it
   }
 
   if (configSave()) {
diff --git a/esp-link/cgiwifi.c b/esp-link/cgiwifi.c
index f15aa21..8ae7e3a 100644
--- a/esp-link/cgiwifi.c
+++ b/esp-link/cgiwifi.c
@@ -279,7 +279,7 @@ void ICACHE_FLASH_ATTR wifiStartScan() {
     cgiWifiAps.scanInProgress = 1;
     os_timer_disarm(&scanTimer);
     os_timer_setfn(&scanTimer, scanStartCb, NULL);
-    os_timer_arm_us(&scanTimer, 200000, 0);
+    os_timer_arm(&scanTimer, 200, 0);
   }
 }
 
@@ -335,7 +335,7 @@ static void ICACHE_FLASH_ATTR resetTimerCb(void *arg) {
       // We're happily connected, go to STA mode
       DBG("Wifi got IP. Going into STA mode..\n");
       wifi_set_opmode(1);
-      os_timer_arm_us(&resetTimer, RESET_TIMEOUT * 1000, 0); // check one more time after switching to STA-only
+      os_timer_arm(&resetTimer, RESET_TIMEOUT, 0); // check one more time after switching to STA-only
 #endif
     }
     log_uart(false);
@@ -349,7 +349,7 @@ static void ICACHE_FLASH_ATTR resetTimerCb(void *arg) {
     }
     log_uart(true);
     DBG("Enabling/continuing uart log\n");
-    os_timer_arm_us(&resetTimer, RESET_TIMEOUT * 1000, 0);
+    os_timer_arm(&resetTimer, RESET_TIMEOUT, 0);
   }
 }
 
@@ -368,7 +368,7 @@ static void ICACHE_FLASH_ATTR reassTimerCb(void *arg) {
   // IP address
   os_timer_disarm(&resetTimer);
   os_timer_setfn(&resetTimer, resetTimerCb, NULL);
-  os_timer_arm_us(&resetTimer, 4*RESET_TIMEOUT * 1000, 0);
+  os_timer_arm(&resetTimer, 4*RESET_TIMEOUT, 0);
 }
 
 // Kick off connection to some network
@@ -380,7 +380,7 @@ void ICACHE_FLASH_ATTR connectToNetwork(char *ssid, char *pass) {
   // Schedule disconnect/connect
   os_timer_disarm(&reassTimer);
   os_timer_setfn(&reassTimer, reassTimerCb, NULL);
-  os_timer_arm_us(&reassTimer, 1000000, 0); // 1 second for the response of this request to make it
+  os_timer_arm(&reassTimer, 1000, 0); // 1 second for the response of this request to make it
 }
 
 // This cgi uses the routines above to connect to a specific access point with the
@@ -527,7 +527,7 @@ int ICACHE_FLASH_ATTR cgiWiFiSpecial(HttpdConnData *connData) {
   // schedule change-over
   os_timer_disarm(&reassTimer);
   os_timer_setfn(&reassTimer, configWifiIP, NULL);
-  os_timer_arm_us(&reassTimer, 1 * 1000000, 0); // 1 second for the response of this request to make it
+  os_timer_arm(&reassTimer, 1000, 0); // 1 second for the response of this request to make it
   // return redirect info
   jsonHeader(connData, 200);
   httpdSend(connData, url, -1);
@@ -700,7 +700,7 @@ int ICACHE_FLASH_ATTR cgiWiFiSetMode(HttpdConnData *connData) {
             wifi_station_connect();
             os_timer_disarm(&resetTimer);
             os_timer_setfn(&resetTimer, resetTimerCb, NULL);
-            os_timer_arm_us(&resetTimer, RESET_TIMEOUT * 1000, 0);
+            os_timer_arm(&resetTimer, RESET_TIMEOUT, 0);
         }
         if(previous_mode == 1){
             // moving to AP or STA+AP from STA, so softap config call needed
@@ -815,7 +815,7 @@ int ICACHE_FLASH_ATTR cgiWiFiConnStatus(HttpdConnData *connData) {
       // Reset into AP-only mode sooner.
       os_timer_disarm(&resetTimer);
       os_timer_setfn(&resetTimer, resetTimerCb, NULL);
-      os_timer_arm_us(&resetTimer, 1 * 1000000, 0);
+      os_timer_arm(&resetTimer, 1000, 0);
     }
   }
 #endif
@@ -959,7 +959,7 @@ void ICACHE_FLASH_ATTR wifiInit() {
     // check on the wifi in a few seconds to see whether we need to switch mode
     os_timer_disarm(&resetTimer);
     os_timer_setfn(&resetTimer, resetTimerCb, NULL);
-    os_timer_arm_us(&resetTimer, RESET_TIMEOUT * 1000, 0);
+    os_timer_arm(&resetTimer, RESET_TIMEOUT, 0);
 }
 
 // Access functions for cgiWifiAps : query the number of entries in the table
diff --git a/esp-link/config.c b/esp-link/config.c
index e3a4fe7..224f047 100644
--- a/esp-link/config.c
+++ b/esp-link/config.c
@@ -34,7 +34,6 @@ FlashConfig flashDefault = {
   .data_bits	= EIGHT_BITS,
   .parity	= NONE_BITS,
   .stop_bits	= ONE_STOP_BIT,
-  .tx_enable_pin = -1,
 };
 
 typedef union {
@@ -161,13 +160,6 @@ bool ICACHE_FLASH_ATTR configRestore(void) {
       flashConfig.parity = flashDefault.parity;
       flashConfig.stop_bits = flashDefault.stop_bits;
   }
-  if (flashConfig.tx_enable_pin == 0 &&
-      (flashConfig.conn_led_pin == 0 || flashConfig.reset_pin == 0 ||
-       flashConfig.isp_pin == 0 || flashConfig.ser_led_pin == 0)) {
-    // just added tx_enable_pin and it got the default 0, which is not good, need to default to
-    // disabled.
-    flashConfig.tx_enable_pin = -1;
-  }
   return true;
 }
 
diff --git a/esp-link/config.h b/esp-link/config.h
index 862bf0c..65195d2 100644
--- a/esp-link/config.h
+++ b/esp-link/config.h
@@ -41,7 +41,6 @@ typedef struct {
   int8_t   data_bits;
   int8_t   parity;
   int8_t   stop_bits;
-  int8_t   tx_enable_pin;
 } FlashConfig;
 extern FlashConfig flashConfig;
 
diff --git a/esp-link/main.c b/esp-link/main.c
index 6f420f2..d2a316e 100644
--- a/esp-link/main.c
+++ b/esp-link/main.c
@@ -161,9 +161,7 @@ user_rf_cal_sector_set(void) {
 // Main routine to initialize esp-link.
 void ICACHE_FLASH_ATTR
 user_init(void) {
-  system_timer_reinit();
-
-// uncomment the following three lines to see flash config messages for troubleshooting
+  // uncomment the following three lines to see flash config messages for troubleshooting
   //uart_init(115200, 115200);
   //logInit();
   //os_delay_us(100000L);
@@ -175,7 +173,7 @@ user_init(void) {
   gpio_output_set(0, 0, 0, (1<<15)); // some people tie it to GND, gotta ensure it's disabled
   // init UART
   uart_init(CALC_UARTMODE(flashConfig.data_bits, flashConfig.parity, flashConfig.stop_bits),
-            flashConfig.baud_rate, flashConfig.tx_enable_pin, 115200);
+            flashConfig.baud_rate, 115200);
   logInit(); // must come after init of uart
   // Say hello (leave some time to cause break in TX after boot loader's msg
   os_delay_us(10000L);
@@ -203,7 +201,7 @@ user_init(void) {
 #ifdef SHOW_HEAP_USE
   os_timer_disarm(&prHeapTimer);
   os_timer_setfn(&prHeapTimer, prHeapTimerCb, NULL);
-  os_timer_arm_us(&prHeapTimer, 10 * 1000000, 1);
+  os_timer_arm(&prHeapTimer, 10 * 1000, 1);
 #endif
 
   struct rst_info *rst_info = system_get_rst_info();
diff --git a/esp-link/status.c b/esp-link/status.c
index 70a96d0..6905850 100644
--- a/esp-link/status.c
+++ b/esp-link/status.c
@@ -92,7 +92,7 @@ static void ICACHE_FLASH_ATTR ledTimerCb(void *v) {
   }
 
   setLed(ledState);
-  os_timer_arm_us(&ledTimer, time * 1000, 0);
+  os_timer_arm(&ledTimer, time, 0);
 }
 
 // change the wifi state indication
@@ -101,7 +101,7 @@ void ICACHE_FLASH_ATTR statusWifiUpdate(uint8_t state) {
   // schedule an update (don't want to run into concurrency issues)
   os_timer_disarm(&ledTimer);
   os_timer_setfn(&ledTimer, ledTimerCb, NULL);
-  os_timer_arm_us(&ledTimer, 500000, 0);
+  os_timer_arm(&ledTimer, 500, 0);
 }
 
 //===== Init status stuff
@@ -117,12 +117,12 @@ void ICACHE_FLASH_ATTR statusInit(void) {
 
   os_timer_disarm(&ledTimer);
   os_timer_setfn(&ledTimer, ledTimerCb, NULL);
-  os_timer_arm_us(&ledTimer, 2 * 1000000, 0);
+  os_timer_arm(&ledTimer, 2000, 0);
 
 #ifdef MQTT
   os_timer_disarm(&mqttStatusTimer);
   os_timer_setfn(&mqttStatusTimer, mqttStatusCb, NULL);
-  os_timer_arm_us(&mqttStatusTimer, MQTT_STATUS_INTERVAL * 1000, 1); // recurring timer
+  os_timer_arm(&mqttStatusTimer, MQTT_STATUS_INTERVAL, 1); // recurring timer
 #endif // MQTT
 }
 
diff --git a/html/home.html b/html/home.html
index 59dc5fd..de9862f 100644
--- a/html/home.html
+++ b/html/home.html
@@ -76,12 +76,6 @@
                   <div class="popup">Second signal to program &#xb5;C.
                     AVR:not used, esp8266:gpio2, ARM:ISP</div>
                 </div>
-                <div class="pure-control-group">
-                  <label for="pin-txen">TX Enable</label>
-                  <select id="pin-txen"></select>
-                  <div class="popup">A pin that should be asserted high while transmitting
-                    (eg. to put RS/485 trancievers into TX mode)</div>
-                </div>
                 <div class="pure-control-group">
                   <label for="pin-conn">Conn LED</label>
                   <select id="pin-conn"></select>
diff --git a/html/ui.js b/html/ui.js
index eb50b4c..67361c9 100644
--- a/html/ui.js
+++ b/html/ui.js
@@ -393,12 +393,12 @@ function showNotification(text) {
 //===== GPIO Pin mux card
 
 var pinPresets = {
-  // array: reset, isp, conn, ser, swap, rxpup, txen
-  "esp-01":       [  0, -1, 2, -1, 0, 1, -1 ],
-  "esp-12":       [ 12, 14, 0,  2, 0, 1, -1 ],
-  "esp-12 swap":  [  1,  3, 0,  2, 1, 1, -1 ],
-  "esp-bridge":   [ 12, 13, 0, 14, 0, 0, -1 ],
-  "wifi-link-12": [  1,  3, 0,  2, 1, 0, -1 ],
+  // array: reset, isp, conn, ser, swap, rxpup
+  "esp-01":       [  0, -1, 2, -1, 0, 1 ],
+  "esp-12":       [ 12, 14, 0,  2, 0, 1 ],
+  "esp-12 swap":  [  1,  3, 0,  2, 1, 1 ],
+  "esp-bridge":   [ 12, 13, 0, 14, 0, 0 ],
+  "wifi-link-12": [  1,  3, 0,  2, 1, 0 ],
 };
 
 function createPresets(sel) {
@@ -418,7 +418,6 @@ function createPresets(sel) {
     setPP("ser",   pp[3]);
     setPP("swap",  pp[4]);
     $("#pin-rxpup").checked = !!pp[5];
-    setPP("txen",  pp[6]);
     sel.value = 0;
   };
 
@@ -454,7 +453,6 @@ function displayPins(resp) {
   createSelectForPin("ser", resp["ser"]);
   $("#pin-swap").value = resp["swap"];
   $("#pin-rxpup").checked = !!resp["rxpup"];
-  createSelectForPin("txen", resp["txen"]);
   createPresets($("#pin-preset"));
 
   $("#pin-spinner").setAttribute("hidden", "");
@@ -471,7 +469,7 @@ function setPins(ev) {
   ev.preventDefault();
   var url = "/pins";
   var sep = "?";
-  ["reset", "isp", "conn", "ser", "swap", "txen"].forEach(function(p) {
+  ["reset", "isp", "conn", "ser", "swap"].forEach(function(p) {
     url += sep + p + "=" + $("#pin-"+p).value;
     sep = "&";
   });
diff --git a/include/esp8266.h b/include/esp8266.h
index 3cb71cf..9531dfe 100644
--- a/include/esp8266.h
+++ b/include/esp8266.h
@@ -18,7 +18,6 @@
 #include <gpio.h>
 #include <mem.h>
 
-#define USE_US_TIMER
 #include <osapi.h>
 #include <upgrade.h>
 
diff --git a/mqtt/mqtt.c b/mqtt/mqtt.c
index f6a557e..cce3436 100644
--- a/mqtt/mqtt.c
+++ b/mqtt/mqtt.c
@@ -703,7 +703,7 @@ MQTT_Connect(MQTT_Client* client) {
   // start timer function to tick every second
   os_timer_disarm(&client->mqttTimer);
   os_timer_setfn(&client->mqttTimer, (os_timer_func_t *)mqtt_timer, client);
-  os_timer_arm_us(&client->mqttTimer, 1 * 1000000, 1);
+  os_timer_arm(&client->mqttTimer, 1000, 1);
 
   // initiate the TCP connection or DNS lookup
   os_printf("MQTT: Connect to %s:%d %p (client=%p)\n",
diff --git a/serial/serbridge.c b/serial/serbridge.c
index 74d1fc1..7ba8e8e 100644
--- a/serial/serbridge.c
+++ b/serial/serbridge.c
@@ -18,7 +18,7 @@
 static struct espconn serbridgeConn1; // plain bridging port
 static struct espconn serbridgeConn2; // programming port
 static esp_tcp serbridgeTcp1, serbridgeTcp2;
-static int8_t mcu_reset_pin, mcu_isp_pin, tx_enable_pin;
+static int8_t mcu_reset_pin, mcu_isp_pin;
 
 uint8_t in_mcu_flashing;   // for disabling slip during MCU flashing
 
@@ -557,10 +557,9 @@ serbridgeInitPins()
 {
   mcu_reset_pin = flashConfig.reset_pin;
   mcu_isp_pin = flashConfig.isp_pin;
-  tx_enable_pin = flashConfig.tx_enable_pin;
 #ifdef SERBR_DBG
-  os_printf("Serbridge pins: reset=%d isp=%d tx_enable=%d swap=%d\n",
-      mcu_reset_pin, mcu_isp_pin, tx_enable_pin, flashConfig.swap_uart);
+  os_printf("Serbridge pins: reset=%d isp=%d swap=%d\n",
+      mcu_reset_pin, mcu_isp_pin, flashConfig.swap_uart);
 #endif
 
   if (flashConfig.swap_uart) {
@@ -579,25 +578,12 @@ serbridgeInitPins()
     system_uart_de_swap();
   }
 
-  /* set both pins to 1 before turning them on (so we don't cause a reset)
-   * then switch pin mux to make these pins GPIO pins
-   */
-  if (mcu_isp_pin >= 0) {
-    GPIO_OUTPUT_SET(mcu_isp_pin, 1);
-    makeGpio(mcu_isp_pin);
-  }
-
-  if (mcu_reset_pin >= 0) {
-    GPIO_OUTPUT_SET(mcu_reset_pin, 1);
-    makeGpio(mcu_reset_pin);
-  }
-
-  // set TX_ENABLE to 0 so we start up listening
-  if (tx_enable_pin >= 0) {
-    GPIO_OUTPUT_SET(tx_enable_pin, 0);
-    makeGpio(tx_enable_pin);
-  }
-  uart0_set_tx_enable_pin(tx_enable_pin); // must set to -1 if that's its value
+  // set both pins to 1 before turning them on so we don't cause a reset
+  if (mcu_isp_pin >= 0)   GPIO_OUTPUT_SET(mcu_isp_pin, 1);
+  if (mcu_reset_pin >= 0) GPIO_OUTPUT_SET(mcu_reset_pin, 1);
+  // switch pin mux to make these pins GPIO pins
+  if (mcu_reset_pin >= 0) makeGpio(mcu_reset_pin);
+  if (mcu_isp_pin >= 0)   makeGpio(mcu_isp_pin);
 }
 
 // Start transparent serial bridge TCP server on specified port (typ. 23)
diff --git a/serial/serled.c b/serial/serled.c
index 8d533e1..5bd66a2 100644
--- a/serial/serled.c
+++ b/serial/serled.c
@@ -25,7 +25,7 @@ void ICACHE_FLASH_ATTR serledFlash(int duration) {
   setSerled(1);
   os_timer_disarm(&serledTimer);
   os_timer_setfn(&serledTimer, serledTimerCb, NULL);
-  os_timer_arm_us(&serledTimer, duration * 1000, 0);
+  os_timer_arm(&serledTimer, duration, 0);
 }
 
 void ICACHE_FLASH_ATTR serledInit(void) {
diff --git a/serial/uart.c b/serial/uart.c
index 2580d3f..cb44ab0 100644
--- a/serial/uart.c
+++ b/serial/uart.c
@@ -28,7 +28,6 @@
 #endif
 
 LOCAL uint8_t uart_recvTaskNum;
-LOCAL int8_t uart0_tx_enable_pin;
 
 // UartDev is defined and initialized in rom code.
 extern UartDevice    UartDev;
@@ -37,53 +36,6 @@ static UartRecv_cb uart_recv_cb[4];
 
 static void uart0_rx_intr_handler(void *para);
 
-/******************************************************************************
- * FunctionName : set_tx_enable_pin
- * Description  : Set which pin to use for RS-485 TX_ENABLE
- * Parameters   : pin, the pin to use
- * Returns      : NONE
-*******************************************************************************/
-void ICACHE_FLASH_ATTR
-uart0_set_tx_enable_pin(int8_t pin) {
-  uart0_tx_enable_pin = pin;
-}
-
-/******************************************************************************
- * FunctionName : tx_enable
- * Description  : Internal used function
- *                Set the TX_ENABLE line for RS-485 communications
- * Parameters   : state, true if the TX_ENABLE line should be asserted high
- * Returns      : NONE
-*******************************************************************************/
-static void ICACHE_FLASH_ATTR
-tx_enable(bool state)
-{
-  if (uart0_tx_enable_pin >= 0) {
-    DBG_UART("TX_ENABLE gpio%d state=%d\n", uart0_tx_enable_pin, (int)state);
-    GPIO_OUTPUT_SET(uart0_tx_enable_pin, (state) ? 1 : 0);
-  } else {
-    DBG_UART("TX Enable: no pin\n");
-  }
-}
-
-os_timer_t uart_tx_enable_timer;
-bool uart_tx_enable_timer_inited = false;
-
-/******************************************************************************
- * FunctionName : tx_completed_interrupt
- * Description  : Internal used function
- *                Set the TX enable line low, after the UART has completed tranmission
- * Parameters   : unused unused
- * Returns      : NONE
-*******************************************************************************/
-static void ICACHE_FLASH_ATTR
-tx_completed_interrupt(void *unused)
-{
-	os_timer_disarm(&uart_tx_enable_timer);
-	tx_enable(false);
-}
-
-
 /******************************************************************************
  * FunctionName : uart_config
  * Description  : Internal used function
@@ -126,20 +78,12 @@ uart_config(uint8 uart_no, UartBautRate baudrate, uint32 conf0)
     // to set the threshold here...
     // We do not enable framing error interrupts 'cause they tend to cause an interrupt avalanche
     // and instead just poll for them when we get a std RX interrupt.
-
-	uint32_t tx_empty_bits = 0;
-	if (uart0_tx_enable_pin >= 0) {
-	  // Set the empty threshold to 0 and enable the buffer empty interrupt
-	  tx_empty_bits = (0 & UART_TXFIFO_EMPTY_THRHD) << UART_TXFIFO_EMPTY_THRHD_S | UART_TXFIFO_EMPTY_INT_ENA;
-	}
     WRITE_PERI_REG(UART_CONF1(uart_no),
                    ((80 & UART_RXFIFO_FULL_THRHD) << UART_RXFIFO_FULL_THRHD_S) |
                    ((100 & UART_RX_FLOW_THRHD) << UART_RX_FLOW_THRHD_S) |
                    UART_RX_FLOW_EN |
                    (4 & UART_RX_TOUT_THRHD) << UART_RX_TOUT_THRHD_S |
-                   UART_RX_TOUT_EN) |
-                   tx_empty_bits
-         ;
+                   UART_RX_TOUT_EN);
     SET_PERI_REG_MASK(UART_INT_ENA(uart_no), UART_RXFIFO_FULL_INT_ENA | UART_RXFIFO_TOUT_INT_ENA);
   } else {
     WRITE_PERI_REG(UART_CONF1(uart_no),
@@ -164,16 +108,7 @@ uart_tx_one_char(uint8 uart, uint8 c)
   //Wait until there is room in the FIFO
   while (((READ_PERI_REG(UART_STATUS(uart))>>UART_TXFIFO_CNT_S)&UART_TXFIFO_CNT)>=100) ;
   //Send the character
-  if (UART0 == uart && uart0_tx_enable_pin >= 0) {
-    // A tx_completed_interrupt may have already been scheduled, cancel it before it fires during our transmission
-	os_timer_disarm(&uart_tx_enable_timer);
-
-    tx_enable(true);
-    WRITE_PERI_REG(UART_FIFO(uart), c);
-    SET_PERI_REG_MASK(UART_INT_ENA(uart), UART_TXFIFO_EMPTY_INT_ENA);
-  } else {
-    WRITE_PERI_REG(UART_FIFO(uart), c);
-  }
+  WRITE_PERI_REG(UART_FIFO(uart), c);
   return OK;
 }
 
@@ -231,7 +166,6 @@ uart0_sendStr(const char *str)
 }
 
 static uint32 last_frm_err; // time in us when last framing error message was printed
-static int uart0_baud_rate = 0; // The baud rate for uart0
 
 /******************************************************************************
  * FunctionName : uart0_rx_intr_handler
@@ -270,13 +204,6 @@ uart0_rx_intr_handler(void *para)
     //DBG_UART("stat:%02X",*(uint8 *)UART_INT_ENA(uart_no));
     ETS_UART_INTR_DISABLE();
     post_usr_task(uart_recvTaskNum, 0);
-  } else if (UART_TXFIFO_EMPTY_INT_ST == (READ_PERI_REG(UART_INT_ST(uart_no)) & UART_TXFIFO_EMPTY_INT_ST)) {
-    // TX Queue is empty, disable the TX_ENABLE line once the transmission is complete
-    CLEAR_PERI_REG_MASK(UART_INT_ENA(UART0), UART_TXFIFO_EMPTY_INT_ENA);
-	if (0 != uart0_baud_rate) {
-	  int tx_char_time = 8 * 1000000 / uart0_baud_rate; // assumes 8 bits per character
-	  os_timer_arm_us(&uart_tx_enable_timer, tx_char_time, false);
-	}
   }
 }
 
@@ -326,7 +253,6 @@ done:
 
 void ICACHE_FLASH_ATTR
 uart0_baud(int rate) {
-  uart0_baud_rate = rate;
   os_printf("UART %d baud\n", rate);
   uart_div_modify(UART0, UART_CLK_FREQ / rate);
 }
@@ -341,18 +267,12 @@ uart0_config(uint8_t data_bits, uint8_t parity, uint8_t stop_bits) {
  * FunctionName : uart_init
  * Description  : user interface for init uart
  * Parameters   : UartBautRate uart0_br - uart0 bautrate
- *                uart0TxEnablePin
  *                UartBautRate uart1_br - uart1 bautrate
  * Returns      : NONE
 *******************************************************************************/
 void ICACHE_FLASH_ATTR
-uart_init(uint32 conf0, UartBautRate uart0_br, int8_t uart0TxEnablePin, UartBautRate uart1_br)
+uart_init(uint32 conf0, UartBautRate uart0_br, UartBautRate uart1_br)
 {
-  uart0_set_tx_enable_pin(uart0TxEnablePin);
-  // Set up a timer to disable the TX line after the last byte has been transmitted
-  os_timer_disarm(&uart_tx_enable_timer);
-  os_timer_setfn(&uart_tx_enable_timer, tx_completed_interrupt, NULL);
-
   // rom use 74880 baut_rate, here reinitialize
   uart_config(UART0, uart0_br, conf0);
   uart_config(UART1, uart1_br, conf0);
diff --git a/serial/uart.h b/serial/uart.h
index a552565..f3fc2de 100644
--- a/serial/uart.h
+++ b/serial/uart.h
@@ -8,7 +8,7 @@ typedef void (*UartRecv_cb)(char *buf, short len);
 
 // Initialize UARTs to the provided baud rates (115200 recommended). This also makes the os_printf
 // calls use uart1 for output (for debugging purposes)
-void uart_init(uint32 conf0, UartBautRate uart0_br, int8_t uart0TxEnablePin, UartBautRate uart1_br);
+void uart_init(uint32 conf0, UartBautRate uart0_br, UartBautRate uart1_br);
 
 // Transmit a buffer of characters on UART0
 void uart0_tx_buffer(char *buf, uint16 len);
@@ -30,6 +30,4 @@ void uart0_baud(int rate);
 void uart0_config(uint8_t data_bits, uint8_t parity, uint8_t stop_bits);
 void uart_config(uint8 uart_no, UartBautRate baudrate, uint32 conf0);
 
-void uart0_set_tx_enable_pin(int8_t pin);
-
 #endif /* __UART_H__ */
diff --git a/syslog/syslog.c b/syslog/syslog.c
index 3c8ae48..5c88901 100644
--- a/syslog/syslog.c
+++ b/syslog/syslog.c
@@ -91,7 +91,7 @@ static void ICACHE_FLASH_ATTR syslog_timer_arm(int delay) {
     syslog_timer_armed = true;
     os_timer_disarm(&wifi_chk_timer);
     os_timer_setfn(&wifi_chk_timer, (os_timer_func_t *)syslog_chk_status, NULL);
-    os_timer_arm_us(&wifi_chk_timer, delay * 1000, 0);
+    os_timer_arm(&wifi_chk_timer, delay, 0);
 }
 
 /******************************************************************************