Maxim-ic)is a very common real time clock that communicates over I2C (which makes it the perfect choice for testing the module we just built). The typical way to handle the 1307 is to write a byte to it to set the internal pointer and then read back multiple bytes of data. Many of the variants contain additional memory that you can use to store your own data, but in general the first 7 or so bytes contain data about the current time. This particular breakout came from Adafruit (one of the good online retailers), but the chips themselves are available. The two resistors next to the ic are the pullups to Vcc, there is also a filter cap, a 32.768kHz crystal and a battery to allow the ic to continue to run where power is otherwise unavailable.
Xilinx). These boards usually have way too many devices that you will never use, but are also usually built very well and have plenty of io to work with...
Texas Instruments is really intended to split the I2C lines to separate Tx/Rx pairs for longer distance communication than the I2C is typically capable of handling. This little chip handles the 5 volt signals from the ds1307 on the bus and the other side can handle a much wider voltage range, and by tying the Tx/Rx pins together we can connect it directly to the fpga. There are many level converters from other companies that work as well, but this is the only one that just always work for me.
open bench logic sniffer) in a breadboard because it's an awful lot easier to use than little clips.