Andrew's git - arduino-weather.git/blob - libraries/OneWire/examples/DS2408_Switch/DS2408

   1#include <OneWire.h>
   2
   3/*
   4 * DS2408 8-Channel Addressable Switch
   5 *
   6 * Writte by Glenn Trewitt, glenn at trewitt dot org
   7 *
   8 * Some notes about the DS2408:
   9 *   - Unlike most input/output ports, the DS2408 doesn't have mode bits to
  10 *       set whether the pins are input or output.  If you issue a read command,
  11 *       they're inputs.  If you write to them, they're outputs.
  12 *   - For reading from a switch, you should use 10K pull-up resisters.
  13 */
  14
  15void PrintBytes(uint8_t* addr, uint8_t count, bool newline=0) {
  16  for (uint8_t i = 0; i < count; i++) {
  17    Serial.print(addr[i]>>4, HEX);
  18    Serial.print(addr[i]&0x0f, HEX);
  19  }
  20  if (newline)
  21    Serial.println();
  22}
  23
  24void ReadAndReport(OneWire* net, uint8_t* addr) {
  25  Serial.print("  Reading DS2408 ");
  26  PrintBytes(addr, 8);
  27  Serial.println();
  28        
  29  uint8_t buf[13];  // Put everything in the buffer so we can compute CRC easily.
  30  buf[0] = 0xF0;    // Read PIO Registers
  31  buf[1] = 0x88;    // LSB address
  32  buf[2] = 0x00;    // MSB address
  33  net->write_bytes(buf, 3);
  34  net->read_bytes(buf+3, 10);     // 3 cmd bytes, 6 data bytes, 2 0xFF, 2 CRC16
  35  net->reset();
  36
  37  if (!OneWire::check_crc16(buf, 11, &buf[11])) {
  38    Serial.print("CRC failure in DS2408 at ");
  39    PrintBytes(addr, 8, true);
  40    return;
  41  }
  42  Serial.print("  DS2408 data = ");
  43  // First 3 bytes contain command, register address.
  44  Serial.println(buf[3], BIN);
  45}
  46
  47OneWire net(10);  // on pin 10
  48
  49void setup(void) {
  50  Serial.begin(9600);
  51}
  52
  53void loop(void) {
  54  byte i;
  55  byte present = 0;
  56  byte addr[8];
  57  
  58  if (!net.search(addr)) {
  59    Serial.print("No more addresses.\n");
  60    net.reset_search();
  61    delay(1000);
  62    return;
  63  }
  64  
  65  if (OneWire::crc8(addr, 7) != addr[7]) {
  66    Serial.print("CRC is not valid!\n");
  67    return;
  68  }
  69  
  70  if (addr[0] != 0x29) {
  71    PrintBytes(addr, 8);
  72    Serial.print(" is not a DS2408.\n");
  73    return;
  74  }
  75
  76  ReadAndReport(&net, addr);
  77}