From ede898fe5f786d261e1b1791ac102e9cf3fa7366 Mon Sep 17 00:00:00 2001 From: Florian Pritz Date: Sun, 28 Jul 2013 14:12:59 +0200 Subject: inital commit Signed-off-by: Florian Pritz --- lib/OneWire/examples/DS250x_PROM/DS250x_PROM.pde | 90 ++++++++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 lib/OneWire/examples/DS250x_PROM/DS250x_PROM.pde (limited to 'lib/OneWire/examples/DS250x_PROM/DS250x_PROM.pde') diff --git a/lib/OneWire/examples/DS250x_PROM/DS250x_PROM.pde b/lib/OneWire/examples/DS250x_PROM/DS250x_PROM.pde new file mode 100644 index 0000000..baa51c8 --- /dev/null +++ b/lib/OneWire/examples/DS250x_PROM/DS250x_PROM.pde @@ -0,0 +1,90 @@ +/* +DS250x add-only programmable memory reader w/SKIP ROM. + + The DS250x is a 512/1024bit add-only PROM(you can add data but cannot change the old one) that's used mainly for device identification purposes + like serial number, mfgr data, unique identifiers, etc. It uses the Maxim 1-wire bus. + + This sketch will use the SKIP ROM function that skips the 1-Wire search phase since we only have one device connected in the bus on digital pin 6. + If more than one device is connected to the bus, it will fail. + Sketch will not verify if device connected is from the DS250x family since the skip rom function effectively skips the family-id byte readout. + thus it is possible to run this sketch with any Maxim OneWire device in which case the command CRC will most likely fail. + Sketch will only read the first page of memory(32bits) starting from the lower address(0000h), if more than 1 device is present, then use the sketch with search functions. + Remember to put a 4.7K pullup resistor between pin 6 and +Vcc + + To change the range or ammount of data to read, simply change the data array size, LSB/MSB addresses and for loop iterations + + This example code is in the public domain and is provided AS-IS. + + Built with Arduino 0022 and PJRC OneWire 2.0 library http://www.pjrc.com/teensy/td_libs_OneWire.html + + created by Guillermo Lovato + march/2011 + + */ + +#include +OneWire ds(6); // OneWire bus on digital pin 6 +void setup() { + Serial.begin (9600); +} + +void loop() { + byte i; // This is for the for loops + boolean present; // device present var + byte data[32]; // container for the data from device + byte leemem[3] = { // array with the commands to initiate a read, DS250x devices expect 3 bytes to start a read: command,LSB&MSB adresses + 0xF0 , 0x00 , 0x00 }; // 0xF0 is the Read Data command, followed by 00h 00h as starting address(the beginning, 0000h) + byte ccrc; // Variable to store the command CRC + byte ccrc_calc; + + present = ds.reset(); // OneWire bus reset, always needed to start operation on the bus, returns a 1/TRUE if there's a device present. + ds.skip(); // Skip ROM search + + if (present == TRUE){ // We only try to read the data if there's a device present + Serial.println("DS250x device present"); + ds.write(leemem[0],1); // Read data command, leave ghost power on + ds.write(leemem[1],1); // LSB starting address, leave ghost power on + ds.write(leemem[2],1); // MSB starting address, leave ghost power on + + ccrc = ds.read(); // DS250x generates a CRC for the command we sent, we assign a read slot and store it's value + ccrc_calc = OneWire::crc8(leemem, 3); // We calculate the CRC of the commands we sent using the library function and store it + + if ( ccrc_calc != ccrc) { // Then we compare it to the value the ds250x calculated, if it fails, we print debug messages and abort + Serial.println("Invalid command CRC!"); + Serial.print("Calculated CRC:"); + Serial.println(ccrc_calc,HEX); // HEX makes it easier to observe and compare + Serial.print("DS250x readback CRC:"); + Serial.println(ccrc,HEX); + return; // Since CRC failed, we abort the rest of the loop and start over + } + Serial.println("Data is: "); // For the printout of the data + for ( i = 0; i < 32; i++) { // Now it's time to read the PROM data itself, each page is 32 bytes so we need 32 read commands + data[i] = ds.read(); // we store each read byte to a different position in the data array + Serial.print(data[i]); // printout in ASCII + Serial.print(" "); // blank space + } + Serial.println(); + delay(5000); // Delay so we don't saturate the serial output + } + else { // Nothing is connected in the bus + Serial.println("Nothing connected"); + delay(3000); + } +} + + + + + + + + + + + + + + + + + -- cgit v1.2.3-24-g4f1b