+ initial version on GH 0.1.03

Author: RobTillaart

sketches/MultiSpeedI2CScanner/MultiSpeedI2CScanner.ino

@@ -0,0 +1,198 @@
+//
+// FILE: MultiSpeedI2CScanner.ino
+// AUTHOR: Rob Tillaart
+// VERSION: 0.1.03
+// PURPOSE: I2C scanner @different speeds
+// DATE: 2013-11-05
+// URL:
+//
+// Released to the public domain
+//
+
+#include <Wire.h>
+#include <Arduino.h>
+
+// scans devices from 50 to 800KHz I2C speeds.
+// lower than 50 is not possible
+// DS3231 RTC works on 800 KHz. TWBR = 2; (?)
+long speed[] = { 
+ 50, 100, 200, 250, 400, 500, 800 };
+const int speeds = sizeof(speed)/sizeof(speed[0]);
+
+// DELAY BETWEEN TESTS
+#define RESTORE_LATENCY 5 // for delay between tests of found devices.
+bool delayFlag = false;
+
+// MINIMIZE OUTPUT
+bool printAll = true;
+bool header = true;
+
+// STATE MACHINE
+enum states {
+ STOP, ONCE, CONT, HELP };
+states state = STOP;
+
+uint32_t startScan;
+uint32_t stopScan;
+
+void setup() 
+{
+ Serial.begin(115200);
+ Wire.begin();
+ displayHelp();
+}
+
+
+void loop() 
+{
+ switch (getCommand())
+ {
+ case 's': 
+ state = ONCE; 
+ break;
+ case 'c': 
+ state = CONT; 
+ break;
+ case 'd': 
+ delayFlag = !delayFlag;
+ Serial.print(F("<delay="));
+ Serial.println(delayFlag?F("5>"):F("0>"));
+ break;
+ case 'e': 
+ // eeprom test TODO
+ break;
+ case 'h': 
+ header = !header;
+ Serial.print(F("<header="));
+ Serial.println(header?F("yes>"):F("no>"));
+ break;
+ case '?': 
+ state = HELP; 
+ break;
+ case 'p': 
+ printAll = !printAll;
+ Serial.print(F("<print="));
+ Serial.println(printAll?F("all>"):F("found>"));
+ break;
+ case 'q': 
+ state = HELP; 
+ break;
+ default:
+ break;
+ }
+
+ switch(state)
+ {
+ case ONCE: 
+ I2Cscan(); 
+ state = HELP;
+ break;
+ case CONT:
+ I2Cscan();
+ delay(1000);
+ break; 
+ case HELP:
+ displayHelp();
+ state = STOP;
+ break;
+ case STOP:
+ break;
+ default: // ignore all non commands
+ break;
+ }
+}
+
+char getCommand()
+{
+ char c = '\0';
+ if (Serial.available())
+ {
+ c = Serial.read();
+ }
+ return c;
+}
+
+void displayHelp()
+{
+ Serial.println(F("\nArduino I2C Scanner - 0.1.03\n"));
+ Serial.println(F("\ts = single scan"));
+ Serial.println(F("\tc = continuous scan - 1 second delay"));
+ Serial.println(F("\tq = quit continuous scan"));
+ Serial.println(F("\td = toggle latency delay between successful tests."));
+ Serial.println(F("\tp = toggle printAll - printFound."));
+ Serial.println(F("\th = toggle header - noHeader."));
+ Serial.println(F("\t? = help - this page"));
+ Serial.println();
+}
+
+
+void I2Cscan()
+{
+ startScan = millis();
+ uint8_t count = 0;
+
+ if (header)
+ {
+ Serial.print(F("TIME\tDEC\tHEX\t"));
+ for (uint8_t s = 0; s < speeds; s++)
+ {
+ Serial.print(F("\t"));
+ Serial.print(speed[s]);
+ }
+ Serial.println(F("\t[KHz]"));
+ for (uint8_t s = 0; s < speeds + 5; s++)
+ {
+ Serial.print(F("--------"));
+ }
+ Serial.println();
+ }
+
+ // TEST
+ for (uint8_t address = 0; address < 128; address++)
+ {
+ bool printLine = printAll;
+ bool found[speeds];
+ bool fnd = false;
+
+ for (uint8_t s = 0; s < speeds ; s++)
+ {
+ TWBR = (F_CPU/(speed[s]*1000) - 16)/2;
+ Wire.beginTransmission (address);
+ found[s] = (Wire.endTransmission () == 0);
+ fnd |= found[s];
+ // give device 5 millis
+ if (fnd && delayFlag) delay(RESTORE_LATENCY);
+ }
+
+ if (fnd) count++;
+ printLine |= fnd;
+
+ if (printLine)
+ {
+ Serial.print(millis());
+ Serial.print(F("\t"));
+ Serial.print(address, DEC);
+ Serial.print(F("\t0x"));
+ Serial.print(address, HEX);
+ Serial.print(F("\t"));
+
+ for (uint8_t s = 0; s < speeds ; s++)
+ {
+ Serial.print(F("\t"));
+ Serial.print(found[s]? F("V"):F("."));
+ }
+ Serial.println();
+ }
+ }
+
+ stopScan = millis();
+ if (header)
+ {
+ Serial.println();
+ Serial.print(count);
+ Serial.print(F(" devices found in "));
+ Serial.print(stopScan - startScan);
+ Serial.println(F(" milliseconds."));
+ }
+}
+