Note:
I personally do not even own a digital scope ... just an old fashioned analogue one. As such when I test bit bang software timing and compliance to data sheet requirements I will make a special test version of my code that implements a loop calling the bit-bang routines over and over again for doing the same transaction. For example....writing address 0x2A of the EEPROM with data of 0x55....in a continuous loop. Note to make sure to have the test version of the software do nothing else but this loop and turn off any interrupts.

I do have a logic analyzer and this can be quite useful for the testing of bitbang routines in cases where it is not possible to create a continuous loop or if the bit-bang sequence is too long to accomodate on an o-scope display (but don't forget that many analogue scopes have a 10X horizontal expand feature that let you see a lot of a waveform in good detail).

Good Luck
Michael Karas