Merge pull request #4 from plampkin/terminology

Updated terminology, add additional descriptions, updated graphics

1 files changed, 25 insertions, 0 deletions

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+# Arduino TinyWire Slave Library
+
+Originals from <http://www.arduino.cc/playground/Code/USIi2c>
+
+Modified to support ATtiny44/84
+
+## NOTE about reliable communication
+
+Since (most of) the ATTinys lack TWI module for implementing all the nitty-gritty of I2C in hardware
+they will have to do some clock-stretching (at least if run at 8MHz, you may get away with more on higher clock speeds)
+as specified in the I2C protocol. However some (especially "bit-banged") master implementations do not
+support clock-streching (looking at you Bus pirate 3.x and [RPI][rpibug]), you will not get reliable communication
+unless your master supports the full I2C protocol spec. There is a [library][pigpio] which can bit-bang I2C correctly on RPI, use that instead of the [buggy hardware][rpibug] (thanks to @brendanarnold for [that tip][pigtip]).
+
+You can use my [Arduino based I2C master][i2crepl] to test your TinyWire code, this uses Bus Pirate semantics
+with Arduinos TWI hardware that is known to implement I2C properly.
+
+[i2crepl]: https://github.com/rambo/I2C/blob/master/examples/i2crepl/i2crepl.ino
+[rpibug]: http://www.advamation.com/knowhow/raspberrypi/rpi-i2c-bug.html
+[pigpio]: http://abyz.co.uk/rpi/pigpio/python.html#bb_i2c_zip
+[pigtip]: https://github.com/rambo/TinyWire/issues/14#issuecomment-125325081
+
+## delayMicroseconds
+
+See this issue: <https://github.com/rambo/TinyWire/issues/8> (remember to declare the function void if you copy-paste it verbatim)