From 4c6444650da3a0aa1e2e9b00f42cc4e2af057fe6 Mon Sep 17 00:00:00 2001 From: Florian Pritz Date: Wed, 18 Jun 2014 11:48:46 +0200 Subject: initial commit Signed-off-by: Florian Pritz --- .../examples/DS2408_Switch/DS2408_Switch.pde | 77 ++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 lib/OneWire/examples/DS2408_Switch/DS2408_Switch.pde (limited to 'lib/OneWire/examples/DS2408_Switch/DS2408_Switch.pde') diff --git a/lib/OneWire/examples/DS2408_Switch/DS2408_Switch.pde b/lib/OneWire/examples/DS2408_Switch/DS2408_Switch.pde new file mode 100644 index 0000000..d171f9b --- /dev/null +++ b/lib/OneWire/examples/DS2408_Switch/DS2408_Switch.pde @@ -0,0 +1,77 @@ +#include + +/* + * 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(10); // on pin 10 + +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); +} -- cgit v1.2.3-24-g4f1b