Changes between Initial Version and Version 1 of MAX6675

Timestamp:

Mar 17, 2009 11:54:27 PM (15 years ago)

Author:

sgk

Comment:

--

MAX6675

@@ +1 @@
+= MAX665 =
+
+== MAX6675.pde ==
+{{{
+#!c
+#include "SPI.h"
+
+#define VCC  8
+#define GND  9
+#define SLAVE  10
+
+void
+setup()
+{
+  pinMode(GND, OUTPUT);
+  pinMode(VCC, OUTPUT);
+  digitalWrite(GND, LOW); 
+  digitalWrite(VCC, HIGH);
+  Serial.begin(9600);
+  SPI_Master.begin(SLAVE);
+}
+
+void
+loop()
+{
+  int value;
+
+  delay(500);
+  SPI_Master.enable(SLAVE);
+  value = SPI_Master.read() << 8;
+  value |= SPI_Master.read();
+  SPI_Master.disable();
+  
+  if ((value & 0x0004) != 0)
+    Serial.println("Error");
+  else
+    Serial.println((value >> 3) * 0.25);
+}
+}}}
+
+== SPI.cpp ==
+{{{
+#!c
+#include "SPI.h"
+
+boolean SPI_Master_Class::initialized_ = false;
+int SPI_Master_Class::enabled_ = -1;
+
+void
+SPI_Master_Class::begin(int slaveselecter) {
+  if (!initialized_) {
+    initialized_ = true;
+    enabled_ = -1;
+    pinMode(SS, OUTPUT);  // Must be set as OUTPUT before SPE is asserted.
+    pinMode(MOSI, OUTPUT);
+    pinMode(MISO, INPUT);
+    digitalWrite(MISO, HIGH);  // Pull-up
+    pinMode(SCK, OUTPUT);
+    SPCR = (1<<SPE)|(1<<MSTR);  // SPE: SPI Enable; MSTR: Master
+    byte garbage;
+    garbage = SPSR;
+    garbage = SPDR;
+  }
+
+  if (slaveselecter != SS)
+    pinMode(slaveselecter, OUTPUT);
+  digitalWrite(slaveselecter, HIGH);  // Disable
+}
+
+void
+SPI_Master_Class::enable(int slaveselecter) {
+  disable();
+  digitalWrite(slaveselecter, LOW);
+  enabled_ = slaveselecter;
+}
+
+void
+SPI_Master_Class::disable() {
+  if (enabled_ >= 0) {
+    digitalWrite(enabled_, HIGH);
+    enabled_ = -1;
+  }
+}
+
+byte
+SPI_Master_Class::write_and_read(byte data) const {
+  SPDR = data;
+  while (!(SPSR & (1<<SPIF)))
+    ;
+  return SPDR;
+}
+
+void
+SPI_Master_Class::write(byte data) const {
+  write_and_read(data);
+}
+
+byte
+SPI_Master_Class::read() const {
+  return write_and_read(0x00);
+}
+
+SPI_Master_Class SPI_Master;
+}}}
+
+== SPI.h ==
+{{{
+#!c
+#ifndef __SPI_H__
+#define __SPI_H__
+
+#include "WProgram.h"
+
+class SPI_Master_Class {
+public:
+  static void begin(int slaveselecter);
+  void enable(int slaveselecter);
+  void disable();
+  byte write_and_read(byte data) const;
+  void write(byte data) const;
+  byte read() const;
+
+private:
+  static boolean initialized_;
+  static const int SS = 10;
+  static const int MOSI = 11;
+  static const int MISO = 12;
+  static const int SCK = 13;
+  static int enabled_;
+};
+
+extern SPI_Master_Class SPI_Master;
+
+#endif //__SPI_H__
+}}}
+