MultiSpeed I2C Scanner - 50,100,200,400 KHz.

Development Libraries
4

Have added some (menu driven) features. When the application starts you get this menu

Arduino I2C Scanner - 0.1.02 

	s = single scan
	c = continuous scan - 1 second delay
	q = quit continuous scan
	d = toggle delay(5) between addresses.
	p = toggle printAll - printFound.
	h = toggle header - noHeader.
	? = help - this page

It can do just a single scan, and it gives output as shown in post above.
A continuous scan, gives the same output with a one second delay in between. This is useful to patch/change address lines to.
To stop the continuous scanning press q (quit).

Then there are three flags that modifies the behaviour.
d: adds 5 millisecond delay between addresses. This is because some devices have a latency and will not react immediately. I'm not happy with this behaviour and it will change in next version.

p: imho the most useful flag, print complete list of addresses or only the ones found. Reduces the output to something the eye can follow.
h: removes the header/footer from the output so only the lines of addresses responding will be shown. Works especially well in combination with p, and I have doubted for some time to combine the p and h flag.

The combination I use often is printFound, noHeader and continuous. It gives output like

Arduino I2C Scanner - 0.1.02

	s = single scan
	c = continuous scan - 1 second delay
	q = quit continuous scan
	d = toggle delay(5) between addresses.
	p = toggle printAll - printFound.
	h = toggle header - noHeader.
	? = help - this page

<print=found>
<header=no>
104	0x68		V	V	V	V	V	V	V
104	0x68		V	V	V	V	V	V	V
104	0x68		V	V	V	V	V	V	V
104	0x68		V	V	V	V	V	V	V
104	0x68		V	V	V	V	V	V	V
104	0x68		V	V	V	V	V	V	V
104	0x68		V	V	V	V	V	V	V
104	0x68		V	V	V	V	V	V	V

One can see the number of columns has changed as I added additional speeds for I2C: 250 and 500 KHz, 2 speeds at which my RTC and EEPROM work quite well. I also tested 1000 KHz and got mixed results. The RTC did not work reliably at that speed.
(I might try 800 KHz, also a perfect divider of 16 MHz.)

Although still work in progress, the tool already met some of its goals. First on my list is to get delay() behaviour right.

As always comments and remarks are welcome.

update: - code (0.1.02 version) removed.