diff --git a/Readme.md b/Readme.md
index d1c6f74..b25231a 100644
--- a/Readme.md
+++ b/Readme.md
@@ -1,6 +1,6 @@
 # Introduction
 
-# Basic
+# Basic General IO configuration
 
 ## Digital outputs
 
@@ -51,7 +51,7 @@ for(int pwm=255; pwm>=0; pwm-=5){
 }
 ```
 
-## Analog readings
+## Analog readings with ADC
 
 ```c
 #include <Arduino.h>
@@ -74,3 +74,147 @@ void loop() {
   delay(100);
 }
 ```
+
+# A general TCLab readings and heater
+```c
+#include<Arduino.h>
+
+// vars and pins at TCLab
+const int LED = 9;
+const int T1 = A0; // temperature sensor T1 input
+const int T2 = A2; // temperature sensor T2 input
+const int Q1 = 3; // PWM at Q1 (output)
+const int Q2 = 5; // PWM at Q2 (output) 
+
+
+// vars and constants:
+int T1Val;
+int T2Val;
+const int nAvg = 10; // samples per reading
+const long BAUD = 115200; // Freq serial comm
+const float factor = 3.3/1024*100; // 3.3V/1024*100
+
+// functions
+
+float readDeg(int channel) {
+  float acc = 0;
+  for(int i=0;i<=nAvg;i++) {
+    acc += analogRead(channel)*factor-50;
+  }
+  return acc/nAvg;
+}
+
+void setHeater(int pin, float value) {
+  // clamp the input value
+  if(value<0) value = 0;
+  if(value>100) value = 100;
+  //convert to pwm 0 - 255
+  int pwm = (int)(value*255.0/100.0+0.5);
+  analogWrite(pin, pwm);
+  analogWrite(LED, pwm);
+}
+
+
+void setup() {
+  // put your setup code here, to run once:
+  pinMode(Q1, OUTPUT);
+  pinMode(Q2, OUTPUT);
+  pinMode(LED, OUTPUT);
+  setHeater(Q1,40);
+  analogReference(EXTERNAL);
+  Serial.begin(BAUD);
+  delay(100);
+  Serial.println("Temps");
+}
+
+void loop() {
+  // put your main code here, to run repeatedly:
+  float t1Val = readDeg(T1);
+  float t2Val = readDeg(T2);
+  Serial.print(t1Val,4); Serial.print(',');
+  Serial.println(t2Val,4);
+  delay(250);
+}
+```
+
+# Serial communication
+
+```c
+#include<Arduino.h>
+
+// vars and pins at TCLab
+const int LED = 9;
+const int T1 = A0; // temperature sensor T1 input
+const int T2 = A2; // temperature sensor T2 input
+const int Q1 = 3; // PWM at Q1 (output)
+const int Q2 = 5; // PWM at Q2 (output) 
+
+
+// vars and constants:
+const int nAvg = 10; // samples per reading
+const long BAUD = 115200; // Freq serial comm
+const float factor = 3.3/1024*100; // 3.3V/1024*100
+
+// functions
+
+float readDeg(int channel) {
+  float acc = 0;
+  for(int i=0;i<=nAvg;i++) {
+    acc += analogRead(channel)*factor-50;
+  }
+  return acc/nAvg;
+}
+
+void setHeater(int pin, float value) {
+  // clamp the input value
+  if(value<0) value = 0;
+  if(value>100) value = 100;
+  //convert to pwm 0 - 255
+  int pwm = (int)(value*255.0/100.0+0.5);
+  analogWrite(pin, pwm);
+  analogWrite(LED, pwm);
+}
+
+
+void setup() {
+  // put your setup code here, to run once:
+  Serial.begin(BAUD);
+  pinMode(Q1, OUTPUT);
+  pinMode(Q2, OUTPUT);
+  pinMode(LED, OUTPUT);
+  analogReference(EXTERNAL);
+  delay(100);
+  //Serial.println("TCLab ready");
+}
+
+void loop() {
+  // put your main code here, to run repeatedly:
+  if(Serial.available()){
+    String cmd = Serial.readStringUntil('\n');
+    cmd.trim();
+
+    if(cmd == "T1"){
+      float T1Val = readDeg(T1);
+      Serial.println(T1Val);
+    }
+    else if(cmd == "T2"){
+      float T2Val = readDeg(T2);
+      Serial.println(T2Val);
+    }
+    else if(cmd.startsWith("Q1 ")){
+      int val = cmd.substring(3).toInt();
+      setHeater(Q1, val);
+    }
+    else if(cmd.startsWith("Q2 ")){
+      int val = cmd.substring(3).toInt();
+      setHeater(Q2, val);
+    } 
+    else if(cmd == "R1"){
+      Serial.println("Not yet");
+    }
+    else {
+      Serial.println("Command Error");
+    }
+  }
+}
+```