commit dc23fd3aa834c3be1294de679a392ab6499d5c09
Author: James Devine <devine.jd@gmail.com>
Date:   Thu Mar 26 13:36:19 2015 -0700

diff --git a/Piinterruptread b/Piinterruptread
new file mode 100644
index 0000000..d1313bf
--- /dev/null
+++ b/Piinterruptread
@@ -0,0 +1,100 @@
+//insert gpl code headers here
+//macro cycle:
+//setup: intitalise, read all devices and send, wait for gps acquisition
+//loop: null
+//interrupt: 
+//1)read in ADC's (direct port sampling)
+//2)read out GPS timestamp (TIMEMARK) and position (UART or SPI)
+//3)read out extra data (temp, pressure, humidity) (I2C)
+//3.1)maybe read some more out of the adc's (3 samples?) direct port sampling, cycle clock
+//4)apply high level trigger (threshold?) test.
+//5)if test is positive then send the output to Pi over rx/tx port 1
+//6)return to waiting state
+
+//define pins for SPI
+#define DATAOUT 11//MOSI
+#define DATAIN  12//MISO 
+#define SPICLOCK  13//sck
+#define SLAVESELECT 10//ss
+
+
+//opcodes
+#define WREN  6
+#define WRDI  4
+#define RDSR  5
+#define WRSR  1
+#define READ  3
+#define WRITE 2
+
+
+byte eeprom_output_data;
+byte eeprom_input_data=0;
+int tempsensor =0;
+int pressuresensor =0;
+int humiditysensor =0;
+byte clr;
+int address=0;
+//data buffer
+char buffer [128];
+
+
+int pin = 13;
+volatile int state = LOW;
+byte adcpt1, adcpt2, adcpt3;
+
+//directly read ports:
+//Port F (8 bits) and Port K (8 bits) and Port A (8 bits) = 24 bits total
+//set into two 
+
+void setup()
+{
+  pinMode(pin, OUTPUT);
+  attachInterrupt(0, blink, CHANGE);
+  Serial.begin(9600);
+
+//read SPI eeprom
+  address = 0; //set the address of the temp sensor here
+  tempsensor = read_eeprom(address);
+  address = 1; //set the address of the pressure sensor here
+  pressuresensor = read_eeprom(address);
+  address = 2; //set the address of the humidity sensor here
+  humiditysensor = read_eeprom(address);
+}
+
+void loop()
+{
+  digitalWrite(pin, state);
+}
+
+void blink()
+{
+  state = !state;
+  adcpt1= PINF;
+  adcpt2= PINK;
+  adcpt3= PINA;
+  Serial.println("done");
+    
+}
+
+char spi_transfer(volatile char data)
+{
+  SPDR = data;                    // Start the transmission
+  while (!(SPSR & (1<<SPIF)))     // Wait the end of the transmission
+  {
+  };
+  return SPDR;                    // return the received byte
+}
+
+byte read_eeprom(int EEPROM_address)
+{
+  //READ EEPROM
+  int data;
+  digitalWrite(SLAVESELECT,LOW);
+  spi_transfer(READ); //transmit read opcode
+  spi_transfer((char)(EEPROM_address>>8));   //send MSByte address first
+  spi_transfer((char)(EEPROM_address));      //send LSByte address
+  data = spi_transfer(0xFF); //get data byte
+  digitalWrite(SLAVESELECT,HIGH); //release chip, signal end transfer
+  return data;
+}
+