I also have several projects with I2C, TTL-RS232, SPI and more.
For years I used the PC-Testinstruments LA1034 for I2C, reasonable
satisfied with it. Biggest disadvantage is that it cannot use a very
large buffer, e.g. only about 30 I2C characters
Recenlty I bought the 4-channel Saleae Logic-4 for ~100 euro. This one
works great, great user-interface, good specs (for me) and also 1 analog
channel. It uses PC memory instead of internal memory and can store much
more info; I stored >1000 Twi characters and did not run into any limits
yet. The number of channels (4) is on the low side, that is why I now
also bought the Saleae Logic-8 (~200 euro) which has 8 channels that can
all be used for analog.
Flip says to use SigRok and Cypress dev board. But the Sigrok site does
not mention support for Cypress dev boards, Flip could you please shwo
the location where you found this info ?