diff --git a/master/master/config.h b/master/master/config.h
--- a/master/master/config.h
+++ b/master/master/config.h
@@ -12,7 +12,18 @@
 #define F_CPU 11059200
 #define MODULE_ID '1'
 
+// --------------------------------------------------------------------------
+// Slave Sensors config (slavesensors.c)
+// --------------------------------------------------------------------------
 
+#define SLAVE0_SENSORS BOARDTEMP
+#define SLAVE1_SENSORS BOARDTEMP | HUMIDITY | TEMPERATURE | PRESSURE | AMBIENTLIGHT
+#define SLAVE2_SENSORS BOARDTEMP | GEIGER
+#define SLAVE3_SENSORS BOARDTEMP | CAMERA
+#define SLAVE4_SENSORS NONE
+#define SLAVE5_SENSORS NONE
+#define SLAVE6_SENSORS NONE
+#define SLAVE7_SENSORS NONE
 
 // --------------------------------------------------------------------------
 // USART config (serial.c)
@@ -62,7 +73,8 @@
 // it is to noise.
 #define APRS_COMMENT    "Trackuino reminder: replace callsign with your own"
 
-
+// Transmit the APRS sentence every X milliseconds
+#define APRS_TRANSMIT_PERIOD 5000
 
 // --------------------------------------------------------------------------
 // Logger config (logger.c)
@@ -73,4 +85,7 @@
 // Written to the beginning of every log file
 #define LOGGER_HEADERTEXT "HAB Control Master - 1.0\n"
 
+// Log to SD card every X milliseconds
+#define LOGGER_RATE 1000 
+
 #endif /* CONFIG_H_ */
\ No newline at end of file
diff --git a/master/master/lib/aprs.c b/master/master/lib/aprs.c
--- a/master/master/lib/aprs.c
+++ b/master/master/lib/aprs.c
@@ -10,9 +10,9 @@
 #include "ax25.h"
 #include <stdio.h>
 
-const char *gps_aprs_lat = "somelatitudesomelatitudesomelatitudesomelatitudesomelatitudesomelatitude";
-const char *gps_aprs_lon = "somelongitudesomelongitudesomelongitudesomelongitudesomelongitudesomelongitude";
-const char *gps_time = "sometimedatasometimedatasometimedatasometimedatasometimedatasometimedata";
+const char *gps_aprs_lat = "omgmylatitude";
+const char *gps_aprs_lon = "omgmylongitude";
+const char *gps_time = "omgmygpstime";
 float gps_altitude = 123.5;
 int gps_course = 5;
 int gps_speed = 13;
diff --git a/master/master/lib/logger.c b/master/master/lib/logger.c
--- a/master/master/lib/logger.c
+++ b/master/master/lib/logger.c
@@ -8,6 +8,7 @@
 #include "../config.h"
 #include <util/delay.h>
 #include <string.h>
+#include <stdio.h>
 #include <avr/pgmspace.h>
 #include <avr/sleep.h>
 #include <avr/eeprom.h>
@@ -119,8 +120,7 @@ void logger_setup()
 	// Write header information
 	logger_log(LOGGER_HEADERTEXT);
 	logger_log("\n-- BEGIN DATA --\n");
-	logger_log("C1, C2, C3, C4, C5, C6\n");
-	
+
 }	
 
 void logger_log(char *buffer) {
diff --git a/master/master/lib/looptime.c b/master/master/lib/looptime.c
--- a/master/master/lib/looptime.c
+++ b/master/master/lib/looptime.c
@@ -8,8 +8,8 @@
 #include "../config.h"
 #include <avr/io.h>
 #include <avr/interrupt.h>
-#include <avr/delay.h>
-extern volatile uint32_t millis = 0; // Milliseconds since initialization
+#include <util/delay.h>
+volatile uint32_t millis = 0; // Milliseconds since initialization
 
 
 
diff --git a/master/master/lib/sd/sd_raw.c b/master/master/lib/sd/sd_raw.c
--- a/master/master/lib/sd/sd_raw.c
+++ b/master/master/lib/sd/sd_raw.c
@@ -191,18 +191,9 @@ uint8_t sd_raw_init()
             (1 << MSTR0) | // Master mode 
             (0 << CPOL0) | // Clock Polarity: SCK low when idle 
             (0 << CPHA0) | // Clock Phase: sample on rising SCK edge 
-            (1 << SPR10);   // Clock Frequency: f_OSC / 128 
-            //(1 << SPR00); // commentnig this out means /64, which gives over 100khz as required
+            (1 << SPR10);   // Clock Frequency: f_OSC / 64 which gives over 100khz required minimum clock
     SPSR0 &= ~(1 << SPI2X0); // No doubled clock frequency 
 
-/*
-	while(1) {
-		SPDR0 = 'a';					//Load byte to Data register
-		while(!(SPSR0 & (1<<SPIF0))); 	// Wait for transmission complete
-	}
-*/
-
-
     /* initialization procedure */
     sd_raw_card_type = 0;
     
diff --git a/master/master/lib/serial.c b/master/master/lib/serial.c
--- a/master/master/lib/serial.c
+++ b/master/master/lib/serial.c
@@ -9,7 +9,6 @@
 #include "../config.h"
 #include <avr/io.h>
 
-
 void serial0_setup() {
 	/* Set baud rate */
 	UBRR0H = (unsigned char)(USART0_BAUD_PRESCALE>>8);
@@ -42,14 +41,26 @@ void serial1_sendChar( unsigned char byt
 	UDR1 = byte;
 }
 
-void serial0_sendString(char* stringPtr){
+unsigned char serial0_readChar()
+{
+	while(!(UCSR0A &(1<<RXC0)));
+	return UDR0;
+}
+
+unsigned char serial1_readChar()
+{
+	while(!(UCSR1A &(1<<RXC1)));
+	return UDR1;
+}
+
+void serial0_sendString(const char* stringPtr){
 	while(*stringPtr != 0x00){
 		serial0_sendChar(*stringPtr);
 		stringPtr++;
 	}
 }
 
-void serial1_sendString(char* stringPtr){
+void serial1_sendString(const char* stringPtr){
 	while(*stringPtr != 0x00){
 		serial1_sendChar(*stringPtr);
 		stringPtr++;
@@ -57,7 +68,7 @@ void serial1_sendString(char* stringPtr)
 }
 
 
-void serial_sendCommand( char moduleID, char sensorID, uint8_t dataLength, char* data )
+void serial_sendCommand( char moduleID, char sensorID, char* data )
 {
 	char checkSum = 0x00; //initialize checksum
 	
@@ -68,11 +79,11 @@ void serial_sendCommand( char moduleID, 
 	serial0_sendChar(sensorID);
 	checkSum+=sensorID;
 	
-	//send each character of data individually
-	for (int i=0; i<dataLength; i++)
-	{
-		serial0_sendChar(data[i]);
-		checkSum+=data[i];
+	// send data, null-terminated
+	while(*data != 0x00){
+		serial0_sendChar(*data);
+		checkSum += *data;
+		data++;
 	}
 	
 	serial0_sendChar(checkSum);
diff --git a/master/master/lib/serial.h b/master/master/lib/serial.h
--- a/master/master/lib/serial.h
+++ b/master/master/lib/serial.h
@@ -17,13 +17,16 @@
 void serial0_sendChar( unsigned char byte );
 void serial1_sendChar( unsigned char byte );
 
+unsigned char serial0_readChar();
+unsigned char serial1_readChar();
+
 void serial0_setup();
 void serial1_setup();
 
-void serial0_sendString(char* stringPtr);
-void serial1_sendString(char* stringPtr);
+void serial0_sendString(const char* stringPtr);
+void serial1_sendString(const char* stringPtr);
 
-void serial_sendCommand( char moduleID, char sensorID, uint8_t dataLength, char* data );
+void serial_sendCommand( char moduleID, char sensorID, char* data );
 void serial_sendResponseData();
 
 
diff --git a/master/master/lib/serparser.c b/master/master/lib/serparser.c
--- a/master/master/lib/serparser.c
+++ b/master/master/lib/serparser.c
@@ -12,18 +12,11 @@
 #define BROADCAST_ADDR 0 //public address
 #include <avr/io.h>
 #include "../config.h"
-
+#include "serial.h"
 //#define DEBUG
 
 // ************* Command Definitions ***************
 
-// Serial Commands
-enum cmd // CMD ID#
-{
-	BOARDTEMP = 0, // 0
-	PRESSURE,      // 1
-};
-
 // Incoming command buffer
 uint8_t buffer[MAX_CMD_LEN+2];
 
@@ -42,21 +35,10 @@ char sensorID;
 //checksum to be calculated and then compared to the received checksum
 char checksumCalc;
 
-/* return char from UART (h/w buffer) */
-uint8_t uart_getchar(void)
-{
-	// Wait for chars
-	/*	while (!(UCSRA & (1<<RXC)))
-	{
-		idle();
-	}
-	return UDR;
-	*/
-	return 0;
-}
-
 /* Process incoming serial data */
-int uart_Parser(void)
+// TODO: Maybe make this suck up the whole buffer if there is more to be had. That would make this much more efficient.
+// we could parse while(SERIAL_RX_HASBYTES && notOverTimeout), don't have it parse for more than 100ms straight or something...
+int serparser_parse(void)
 {
 
 	char byte;
@@ -65,7 +47,7 @@ int uart_Parser(void)
 	{
 		
 		// Pull byte off of the buffer
-		byte = uart_getchar();
+		byte = serial0_readChar();
 		buffer[bufferPosition] = byte;
 		
 		// byte checking/validation
@@ -108,6 +90,7 @@ int uart_Parser(void)
 			if (byte == ']') //this is the end of the transmission
 			{
 				bufferPosition = 0;
+				return 2; // got whole msg
 			}
 			else //still receiving data
 			{
diff --git a/master/master/lib/serparser.h b/master/master/lib/serparser.h
--- a/master/master/lib/serparser.h
+++ b/master/master/lib/serparser.h
@@ -9,17 +9,7 @@
 #ifndef SERPARSER_H_
 #define SERPARSER_H_
 
-
 // Prototypes
-uint8_t convertchar(uint8_t);
-uint8_t uart_getchar(void);
-void got_char(uint8_t);
-int uart_machine(void);
-void uart_putchar(uint8_t);
-void exec_cmd(void);
-void idle(void);
-void uart_init(void);
-
-
+int serparser_parse(void);
 
 #endif /* SERPARSER_H_ */
\ No newline at end of file
diff --git a/master/master/lib/slavesensors.c b/master/master/lib/slavesensors.c
new file mode 100644
--- /dev/null
+++ b/master/master/lib/slavesensors.c
@@ -0,0 +1,86 @@
+/*
+ * slavesensors.c
+ *
+ * Created: 11/27/2012 9:02:12 PM
+ *  Author: ethanzonca
+ */ 
+
+#include <avr/io.h>
+#include <stdbool.h>
+#include "../config.h"
+#include "serial.h"
+#include "serparser.h"
+
+// Serial Commands
+enum sensorTypes // CMD ID#
+{
+	NONE = 0,
+	BOARDTEMP = (1<<0),
+	PRESSURE = (1<<1),
+	GEIGER = (1<<2),
+	TEMPERATURE = (1<<3),
+	HUMIDITY = (1<<4),
+	AMBIENTLIGHT = (1<<5),
+	CAMERA = (1<<5),
+};
+
+uint8_t receptionFinished = 0;
+uint8_t currentSlave = 0;
+uint8_t currentSlaveSensor = 0;
+
+uint8_t maxSlave = 8;
+uint16_t slaves[8];
+
+void slavesensors_setup() 
+{
+	// Empty array
+	for(int i=0; i<8; i++) 
+	{
+		slaves[i] = 0;
+	}	
+	
+	// Configure sensors
+	slaves[0] = SLAVE0_SENSORS;
+	slaves[1] = SLAVE1_SENSORS;
+	slaves[2] = SLAVE2_SENSORS;
+	slaves[3] = SLAVE3_SENSORS;
+	slaves[4] = SLAVE4_SENSORS;
+	slaves[5] = SLAVE5_SENSORS;
+	slaves[6] = SLAVE6_SENSORS;
+	slaves[7] = SLAVE7_SENSORS;	
+}
+
+bool slavesensors_process() 
+{
+	// Periodic: Every Iteration
+		
+	// maybe we should do this in an ISR on byte received. only problem is that this could interrupt things,
+	// but we only care about interruption during logging and such. don't log when parsing a message?
+	receptionFinished = serparser_parse();
+		
+	// Finished reception of a message (one sensor data value). If not finished, send out command to get the next one
+	if(receptionFinished == 2)
+	{
+		bool weFinishedTHeLastSlaveSensor = false; // ex.
+		// if we finished the final reception for this slave, set gettingValues = false;
+		if(currentSlave >= maxSlave && weFinishedTHeLastSlaveSensor)
+		{
+			currentSlave = 0;
+			return false; // We're done for now!
+		}
+		else
+		{
+			// Request data from the next slave
+			currentSlave++;
+			
+			// Need to check the next bit over to see if it has that...
+			
+			serial_sendCommand(currentSlave, 'a', ""); // send req for data
+			return true; // Keep going...
+		}
+	}
+	else 
+	{
+		return true; // Keep going...
+	}
+}		
\ No newline at end of file
diff --git a/master/master/lib/slavesensors.h b/master/master/lib/slavesensors.h
new file mode 100644
--- /dev/null
+++ b/master/master/lib/slavesensors.h
@@ -0,0 +1,18 @@
+/*
+ * slavesensors.h
+ *
+ * Created: 11/27/2012 9:05:47 PM
+ *  Author: ethanzonca
+ */ 
+
+
+#ifndef SLAVESENSORS_H_
+#define SLAVESENSORS_H_
+
+#include <stdbool.h>
+
+void slavesensors_setup();
+bool slavesensors_process();
+
+
+#endif /* SLAVESENSORS_H_ */
\ No newline at end of file
diff --git a/master/master/master.c b/master/master/master.c
--- a/master/master/master.c
+++ b/master/master/master.c
@@ -17,6 +17,8 @@
 #include <util/delay.h>
 #include <avr/wdt.h>
 #include <avr/interrupt.h>
+#include <stdio.h>
+#include <stdbool.h>
 
 #include "lib/serial.h"
 #include "lib/aprs.h"
@@ -26,6 +28,7 @@
 #include "lib/watchdog.h"
 #include "lib/sd/sd_raw_config.h"
 #include "lib/looptime.h"
+#include "lib/slavesensors.h"
 
 void micro_setup() {
 
@@ -34,53 +37,75 @@ void micro_setup() {
 int main(void)
 {
     
-	// Initialize. If this takes more than 4 seconds, be sure to reset the WDT
+	// Initialize libraries
 	time_setup();
 	micro_setup();
 	watchdog_setup();
 	led_setup();
-	serial0_setup(); // Config serial ports
-	serial1_setup(); // Config serial ports
-	logger_setup(); // this takes a few ms
-	afsk_setup(); // can take a few ms
+	serial0_setup();
+	serial1_setup();
+	slavesensors_setup();
+	logger_setup();
+	afsk_setup();
 
 	serial0_sendString("\r\n\r\n---------------------------------\r\nHAB Controller 1.0 - Initialized!\r\n---------------------------------\r\n\r\n");
 	
 	led_on(POWER);
+		
+	// Buffer for string operations
+	char logbuf[32];
+	const char* logBufPtr = logbuf;
 	
-	uint16_t ctr1 = 0;
-	uint16_t ctr2 = 255;
-		
-	char logbuf[32];
-	
+	// Software timers	
 	uint32_t lastAprsBroadcast = 0;
 	uint32_t lastLog = 0;
 	
+	// If we are currently processing sensor data
+	bool isProcessing = false;
+	
+	// Write CSV header to SD card
+	logger_log("ProgramTime,LastAprsBroadcast,LastLog\n");
+	
 	while(1)
     {
 		
-		if(time_millis() - lastLog > 1000) {
+		// Periodic: Logging
+		if(time_millis() - lastLog > LOGGER_RATE) {
+			
+			// TODO: Acquire data from daughterboards
+			//       This will be complicated because we need timeouts / unreliable transmission, etc
+			//
+			// For each daughterboard...
+			//   1. Send request to daughterboard for sensor data
+			//   2. Wait for response from daughterboard (timeout!)
+			//   3. Put data into local variables for transmission / logging
+			
 			led_on(STAT);
-			sprintf(logbuf, "%lu,%u,%u,%u,%u,%u\r\n", time_millis(),5*ctr1,ctr2, 12*ctr2,43*ctr1,5*ctr2);
+			snprintf(logbuf, 32, "%lu,%lu,%lu,\r\n", time_millis(), lastAprsBroadcast,lastLog);
 			logger_log(logbuf);
 			serial0_sendString("SD Logger: ");
-			serial0_sendString(logbuf);
+			serial0_sendString(logBufPtr);
 			led_off(STAT);
 			lastLog = time_millis();
 		}		
 		
-		// 8 second periodic for APRS transmission
-		// for some reason this seems to lock up and the WDT resets everything when the period exceeds 8 seconds. Which is the WDTimeout. Weird.
-		// If we want ~8+ seconds, then we'll need to do something fun here. Maybe reset the wdt...
-		if(time_millis() - lastAprsBroadcast > 10000) {
+		// Periodic: APRS transmission
+		if(time_millis() - lastAprsBroadcast > APRS_TRANSMIT_PERIOD) {
 			while(afsk_busy());
 			aprs_send(); // non-blocking
 			serial0_sendString("Initiating APRS transmission...\r\n");
+			
+			// Start getting values for next transmission
+			isProcessing = true;
+			
 			lastAprsBroadcast = time_millis();
 		}			
 		
-		ctr1++;
-		ctr2-=6;
+		// keep calling processSensors until it is finished
+		if(isProcessing) 
+		{
+			isProcessing = slavesensors_process();
+		}
 		wdt_reset();
     }
 }
\ No newline at end of file
diff --git a/master/master/master.cproj b/master/master/master.cproj
--- a/master/master/master.cproj
+++ b/master/master/master.cproj
@@ -198,6 +198,12 @@
     <Compile Include="lib\serparser.h">
       <SubType>compile</SubType>
     </Compile>
+    <Compile Include="lib\slavesensors.c">
+      <SubType>compile</SubType>
+    </Compile>
+    <Compile Include="lib\slavesensors.h">
+      <SubType>compile</SubType>
+    </Compile>
     <Compile Include="lib\trackuinoGPS\config.h">
       <SubType>compile</SubType>
     </Compile>