--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Small_CPU/Src/uartProtocol_Co2.c	Mon Aug 07 20:29:44 2023 +0200
@@ -0,0 +1,207 @@
+/**
+  ******************************************************************************
+  * @file    uartProtocol_Co2.c
+  * @author  heinrichs weikamp gmbh
+  * @version V0.0.1
+  * @date    31-Jul-2023
+  * @brief   Interface functionality to external, UART based CO2 sensors
+  *
+  @verbatim
+
+
+  @endverbatim
+  ******************************************************************************
+  * @attention
+  *
+  * <h2><center>&copy; COPYRIGHT(c) 2023 heinrichs weikamp</center></h2>
+  *
+  ******************************************************************************
+  */
+/* Includes ------------------------------------------------------------------*/
+
+#include <string.h>
+#include <uartProtocol_Co2.h>
+#include "uart.h"
+#include "externalInterface.h"
+
+
+#ifdef ENABLE_CO2_SUPPORT
+static uint8_t CO2Connected = 0;						/* Binary indicator if a sensor is connected or not */
+static receiveState_t rxState = RX_Ready;
+
+
+
+float LED_Level = 0.0;							/* Normalized LED value which may be used as indication for the health status of the sensor */
+float LED_ZeroOffset = 0.0;
+float pCO2 = 0.0;
+
+
+
+void uartCo2_SendCmd(uint8_t CO2Cmd, uint8_t *cmdString, uint8_t *cmdLength)
+{
+	switch (CO2Cmd)
+	{
+		case CO2CMD_MODE_POLL:		*cmdLength = snprintf((char*)cmdString, 10, "K 2\r\n");
+				break;
+		case CO2CMD_MODE_STREAM:	*cmdLength = snprintf((char*)cmdString, 10, "K 1\r\n");
+				break;
+		case CO2CMD_CALIBRATE:		*cmdLength = snprintf((char*)cmdString, 10, "G\r\n");
+				break;
+		case CO2CMD_GETDATA:		*cmdLength = snprintf((char*)cmdString, 10, "Q\r\n");
+				break;
+		case CO2CMD_GETSCALE:		*cmdLength = snprintf((char*)cmdString, 10, ".\r\n");
+				break;
+		default: *cmdLength = 0;
+			break;
+	}
+	if(cmdLength != 0)
+	{
+		UART_SendCmdString(cmdString);
+	}
+}
+
+
+void uartCo2_Control(void)
+{
+	static uint8_t cmdString[10];
+	static uint8_t cmdLength = 0;
+	static uint8_t lastComState = 0;
+
+	uint8_t activeSensor = externalInterface_GetActiveUartSensor();
+	uartCO2Status_t localComState = externalInterface_GetSensorState(activeSensor + EXT_INTERFACE_MUX_OFFSET);
+
+	uint8_t *pmap = externalInterface_GetSensorMapPointer(0);
+
+
+	if(localComState == UART_CO2_ERROR)
+	{
+		localComState = lastComState;
+	}
+
+	if(localComState == UART_CO2_INIT)
+	{
+		externalInterface_SetCO2Scale(0.0);
+		UART_StartDMA_Receiption();
+		localComState = UART_CO2_SETUP;
+	}
+	if(localComState == UART_CO2_SETUP)
+	{
+		if(externalInterface_GetCO2Scale() == 0.0)
+		{
+			uartCo2_SendCmd(CO2CMD_GETSCALE, cmdString, &cmdLength);
+		}
+		else
+		{
+			localComState = UART_CO2_IDLE;
+		}
+	}
+	else
+	{
+		if(localComState == UART_CO2_CALIBRATE)
+		{
+			uartCo2_SendCmd(CO2CMD_CALIBRATE, cmdString, &cmdLength);
+		}
+		else if(pmap[EXT_INTERFACE_SENSOR_CNT-1] == SENSOR_MUX)		/* sensor is working in polling mode if mux is connected to avoid interference with other sensors */
+		{
+			//if(cmdLength == 0)							/* poll data */
+			if(localComState == UART_CO2_IDLE)
+			{
+				uartCo2_SendCmd(CO2CMD_GETDATA, cmdString, &cmdLength);
+				localComState = UART_CO2_OPERATING;
+			}
+			else											/* resend last command */
+			{
+				UART_SendCmdString(cmdString);
+				cmdLength = 0;
+			}
+		}
+		else
+		{
+			localComState = UART_CO2_OPERATING;					/* sensor in streaming mode if not connected to mux => operating */
+		}
+	}
+	lastComState = localComState;
+	externalInterface_SetSensorState(activeSensor + EXT_INTERFACE_MUX_OFFSET,localComState);
+}
+
+
+void uartCo2_ProcessData(uint8_t data)
+{
+	static uint8_t dataType = 0;
+	static uint32_t dataValue = 0;
+	uint8_t activeSensor = externalInterface_GetActiveUartSensor();
+	uartCO2Status_t localComState = externalInterface_GetSensorState(activeSensor + EXT_INTERFACE_MUX_OFFSET);
+
+	if(rxState == RX_Ready)		/* identify data content */
+	{
+		switch(data)
+		{
+			case 'G':
+			case 'l':
+			case 'D':
+			case 'Z':
+			case '.':			dataType = data;
+								rxState = RX_Data0;
+								dataValue = 0;
+				break;
+			case '?':			localComState = UART_CO2_ERROR;
+				break;
+			default:			/* unknown or corrupted => ignore */
+					break;
+		}
+	}
+	else if((data >= '0') && (data <= '9'))
+	{
+		if((rxState >= RX_Data0) && (rxState <= RX_Data4))
+		{
+			dataValue = dataValue * 10 + (data - '0');
+			rxState++;
+			if(rxState == RX_Data5)
+			{
+				rxState = RX_DataComplete;
+				CO2Connected = 1;
+			}
+		}
+		else	/* protocol error data has max 5 digits */
+		{
+			rxState = RX_Ready;
+		}
+	}
+	if((data == ' ') || (data == '\n'))	/* Abort data detection */
+	{
+		if(rxState == RX_DataComplete)
+		{
+			localComState = UART_CO2_IDLE;
+			if(externalInterface_GetCO2State() == 0)
+			{
+				externalInterface_SetCO2State(EXT_INTERFACE_33V_ON);
+			}
+			switch(dataType)
+			{
+				case 'D':			externalInterface_SetCO2SignalStrength(dataValue);
+					break;
+				case 'l':			LED_ZeroOffset = dataValue;
+					break;
+				case 'Z':			externalInterface_SetCO2Value(dataValue);
+					break;
+				case '.':			externalInterface_SetCO2Scale(dataValue);
+					break;
+				default:			rxState = RX_Ready;
+					break;
+			}
+		}
+		if(rxState != RX_Data0)	/* reset state machine because message in wrong format */
+		{
+			rxState = RX_Ready;
+		}
+	}
+	externalInterface_SetSensorState(activeSensor + EXT_INTERFACE_MUX_OFFSET,localComState);
+}
+
+uint8_t uartCo2_isSensorConnected()
+{
+	return CO2Connected;
+}
+
+#endif
+