Add a version of OneWire library adapted for ESP8266

libraries/OneWire/examples/DS2408_Switch/DS2408_Switch.pde

@@ -0,0 +1,77 @@
+#include <OneWire.h>
+
+/*
+ * DS2408 8-Channel Addressable Switch
+ *
+ * Writte by Glenn Trewitt, glenn at trewitt dot org
+ *
+ * Some notes about the DS2408:
+ *   - Unlike most input/output ports, the DS2408 doesn't have mode bits to
+ *       set whether the pins are input or output.  If you issue a read command,
+ *       they're inputs.  If you write to them, they're outputs.
+ *   - For reading from a switch, you should use 10K pull-up resisters.
+ */
+
+void PrintBytes(uint8_t* addr, uint8_t count, bool newline=0) {
+  for (uint8_t i = 0; i < count; i++) {
+    Serial.print(addr[i]>>4, HEX);
+    Serial.print(addr[i]&0x0f, HEX);
+  }
+  if (newline)
+    Serial.println();
+}
+
+void ReadAndReport(OneWire* net, uint8_t* addr) {
+  Serial.print("  Reading DS2408 ");
+  PrintBytes(addr, 8);
+  Serial.println();
+	
+  uint8_t buf[13];  // Put everything in the buffer so we can compute CRC easily.
+  buf[0] = 0xF0;    // Read PIO Registers
+  buf[1] = 0x88;    // LSB address
+  buf[2] = 0x00;    // MSB address
+  net->write_bytes(buf, 3);
+  net->read_bytes(buf+3, 10);     // 3 cmd bytes, 6 data bytes, 2 0xFF, 2 CRC16
+  net->reset();
+
+  if (!OneWire::check_crc16(buf, 11, &buf[11])) {
+    Serial.print("CRC failure in DS2408 at ");
+    PrintBytes(addr, 8, true);
+    return;
+  }
+  Serial.print("  DS2408 data = ");
+  // First 3 bytes contain command, register address.
+  Serial.println(buf[3], BIN);
+}
+
+OneWire net(2);  // on pin 2
+
+void setup(void) {
+  Serial.begin(9600);
+}
+
+void loop(void) {
+  byte i;
+  byte present = 0;
+  byte addr[8];
+  
+  if (!net.search(addr)) {
+    Serial.print("No more addresses.\n");
+    net.reset_search();
+    delay(1000);
+    return;
+  }
+  
+  if (OneWire::crc8(addr, 7) != addr[7]) {
+    Serial.print("CRC is not valid!\n");
+    return;
+  }
+  
+  if (addr[0] != 0x29) {
+    PrintBytes(addr, 8);
+    Serial.print(" is not a DS2408.\n");
+    return;
+  }
+
+  ReadAndReport(&net, addr);
+}