Hi there, I assume you’re referring to this question in the lesson?
A binary message consisting of four bits was sent to you by a friend. The message was supposed to be ABAB. Unfortunately, your friend set the bit on the wire once every 2 seconds, but you read the wire once every second. Assuming that the first bit was sent and read at the same time, what message did you receive instead?
And that your question is a slight variation which is that if the friend sent a bit every 1/2 second instead what would that look like. I’d recommend “drawing” it out similar to the solution to the original question here does and plot out the setting and reading.
person 1(set 2 bits every second) A-B-|A-B-|-------------
person 2(read 1 bit every second) ^------^------^------^
So if the reader is still expecting 4 bits and reads one bit every second, they’d get AABB because the last bit set on the wire was B and even though the setter is done, the wire keeps state B.
Hope that helps!
Sarah