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authorFlorian Pritz <bluewind@xinu.at>2013-07-28 14:12:59 +0200
committerFlorian Pritz <bluewind@xinu.at>2013-07-28 14:12:59 +0200
commitede898fe5f786d261e1b1791ac102e9cf3fa7366 (patch)
treecd5a11dd12e786078b18294ae65c16d48d10b9f2 /lib/OneWire/examples/DS2408_Switch
downloadtemp-logger-ede898fe5f786d261e1b1791ac102e9cf3fa7366.tar.gz
temp-logger-ede898fe5f786d261e1b1791ac102e9cf3fa7366.tar.xz
inital commit
Signed-off-by: Florian Pritz <bluewind@xinu.at>
Diffstat (limited to 'lib/OneWire/examples/DS2408_Switch')
-rw-r--r--lib/OneWire/examples/DS2408_Switch/DS2408_Switch.pde77
1 files changed, 77 insertions, 0 deletions
diff --git a/lib/OneWire/examples/DS2408_Switch/DS2408_Switch.pde b/lib/OneWire/examples/DS2408_Switch/DS2408_Switch.pde
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index 0000000..d171f9b
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+++ b/lib/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(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);
+}