Also propably needs a MAX2323 to work.

STM32_CONTROL/.vscode/extensions.json

@@ -0,0 +1,10 @@
+{
+    // See http://go.microsoft.com/fwlink/?LinkId=827846
+    // for the documentation about the extensions.json format
+    "recommendations": [
+        "platformio.platformio-ide"
+    ],
+    "unwantedRecommendations": [
+        "ms-vscode.cpptools-extension-pack"
+    ]
+}

STM32_CONTROL/platformio.ini

@@ -13,6 +13,8 @@ platform = ststm32
 board = genericSTM32F103C6
 framework = arduino
 lib_deps = adafruit/DHT sensor library@^1.4.6
+debug_tool = stlink
 upload_protocol = stlink
 ; Enable RX and TX 3
-; build_flags = -D SERIAL_USB -D ENABLE_HWSERIAL3
+; build_flags = -D SERIAL_USB -D ENABLE_HWSERIAL1 -D ENABLE_HWSERIAL2
+; build_flags = -DENABLE_HWSERIAL1 

STM32_CONTROL/src/test.cpp

@@ -0,0 +1,22 @@
+#include <Arduino.h>
+
+
+// UART2 (PA3 = RX, PA2 = TX)
+HardwareSerial mdSerial(PA10, PA9);
+// HardwareSerial sigma(PA9, )
+
+
+
+void setup() {
+
+  mdSerial.begin(38400);
+
+
+
+}
+
+void loop() {
+  mdSerial.write("skibidi");
+
+  delay(5000); // wait before next loop
+}

STM32_CONTROL/versions/main.cpp

@@ -6,7 +6,9 @@ const int MD1200BAUDS = 38400;  // From what I've read it is always 38400
 //const int EPYSLEEPY = 600000;  / 10 minutes
 const int EPYSLEEPY = 300000;  // 5 minutes
 //const int EPYSLEEPY = 150000;  // 2,5 minutes
-HardwareSerial Serial1(31, 30);
+HardwareSerial MDSerial(PA3, PA2);  // Rx Tx
+HardwareSerial DeBug(PA10, PA9);  // Rx Tx
+// HardwareSerial DeBug(USART1);  // use USART1 
 
 // declarations
 int getTemp();
@@ -14,19 +16,23 @@ int setFanTrsh(int);
 
 void setup() {
   // Setup connection to MD1200
-  // Serial1 because we're using RX/TX pins
+  // MDSerial because we're using RX/TX pins
-  Serial1.begin(MD1200BAUDS);
+  MDSerial.begin(MD1200BAUDS);
 
   // Just debug
-  Serial.begin(9600);
+  DeBug.begin(9600);
-  Serial.print("skibidi");
+  DeBug.println("skibidi");
+  delay(15000);
 }
 
 void loop() {
 
+  DeBug.println("Starting loop");
+
   int fanPercnt = getTemp();
   
   if (fanPercnt < 10) {
+    DeBug.println("Executing setFanTrsh");
     setFanTrsh(fanPercnt);
   }
 
@@ -35,11 +41,12 @@ void loop() {
   set fan speed every X minutes
   */
   delay(EPYSLEEPY);
-
+  DeBug.println("Ending loop");
 }
 
 // Get current temperature 
 int getTemp() {
+  DeBug.println("Getting Temperature");
 
   int bp1 = 0;
   int bp2 = 0;
@@ -49,13 +56,13 @@ int getTemp() {
   int simm1 = 0;
   String MD1200output;
   
-  Serial1.println("_temp_rd");
+  MDSerial.println("_temp_rd");
 
   // wait for MD1200 to answer
   delay(30);
-  
+  DeBug.println("getTemp logic start");  
-  while (Serial1.available()) {
+  while (MDSerial.available()) {
-    MD1200output = Serial1.readStringUntil('\n');
+    MD1200output = MDSerial.readStringUntil('\n');
 
     // Check backplane 1
     if (MD1200output.startsWith("BP_1")) {
@@ -126,6 +133,7 @@ int getTemp() {
 
     // Stop when prompt returns
     if (MD1200output.endsWith(">")) {
+      DeBug.println("getTemp got all temp info");
       break;
     }
   }
@@ -138,6 +146,7 @@ int getTemp() {
     int outPrcntg = 21;
 
     // a 
+    DeBug.println("getTemp choosing fan speed");
     switch (bpAvg) {
       case 23:
         outPrcntg = 21;
@@ -170,8 +179,11 @@ int getTemp() {
       
       default:
         return -1;
+        DeBug.println("getTemp error returning -1");
+
     
     }
+      DeBug.println("getTemp return " + String(outPrcntg));
 
     return outPrcntg;
 
@@ -195,9 +207,9 @@ int getTemp() {
 int setFanTrsh(int fanTrshInp) {
   String outputStatement = "set_speed " + String(fanTrshInp);
 
-  Serial.println("Sending " + outputStatement + " to MD1200");
+  DeBug.println("Sending " + outputStatement + " to MD1200");
 
-  if (Serial1.println(outputStatement)) {
+  if (MDSerial.println(outputStatement)) {
     return 1;
   }
   else {

STM32_CONTROL/versions/main.dht22.cpp

@@ -2,6 +2,7 @@
 #include <Adafruit_Sensor.h>
 #include <DHT.h>
 #include <DHT_U.h>
+#include <HardwareSerial.h>
 
 // -------------------------------------------------------------
 // DHT PreConfiguration
@@ -22,6 +23,7 @@ const int MD1200BAUDS = 38400;  // From what I've read it is always 38400
 //const int EPYSLEEPY = 600000;  / 10 minutes
 const int EPYSLEEPY = 300000;  // 5 minutes
 //const int EPYSLEEPY = 150000;  // 2,5 minutes
+HardwareSerial MDSerial(PA3, PA2);  // Rx Tx
 
 // declarations
 int getTemp();
@@ -30,8 +32,8 @@ float dhtRead();
 
 void setup() {
   // Setup connection to MD1200
-  // Serial1 because we're using RX/TX pins
+  // MDSerial because we're using RX/TX pins
-  Serial1.begin(MD1200BAUDS);
+  MDSerial.begin(MD1200BAUDS);
 
   // Just debug
   Serial.begin(9600);
@@ -66,13 +68,13 @@ int getTemp() {
   int simm1 = 0;
   String MD1200output;
   
-  Serial1.println("_temp_rd");
+  MDSerial.println("_temp_rd");
 
   // wait for MD1200 to answer
   delay(30);
   
-  while (Serial1.available()) {
+  while (MDSerial.available()) {
-    MD1200output = Serial1.readStringUntil('\n');
+    MD1200output = MDSerial.readStringUntil('\n');
 
     // Check backplane 1
     if (MD1200output.startsWith("BP_1")) {
@@ -221,7 +223,7 @@ int setFanTrsh(int fanTrshInp) {
 
   Serial.println("Sending " + outputStatement + " to MD1200");
 
-  if (Serial1.println(outputStatement)) {
+  if (MDSerial.println(outputStatement)) {
     return 1;
   }
   else {