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ABCD Message
Week 21
You are exploring an old engineering warehouse and notice this long binary string printed on a piece of paper which you predict is at least 50 years old:
There is also this link, which you decide to visit - the format seems to be the same, though unfortunately you don't have any more info
Can you decode the first message? A reminder, if you are completely stuck, hints will be released after 24 hours :)
Hints
Hints will be released at the start of each of the following days - e.g. the start of day 3 is 48 hours after the challenge starts
| Release Day | Hint |
|---|---|
| 2 | Sometimes the clue is in the title |
| 3 | The title can be read as "A BCD Message" |
| 4 | If you visit the warehouse link in this challenge and refresh it, what happens? |
| 5 | The least significant bits seem to increment slowly, while everything else stays the same, including the length - this string is simply the current UTC time encoded as packed BCD |
| 6 | If you decode the string according to packed BCD rules, then you almost get the correct answer - you notice the 2nd nibble is 1111, which is not a valid BCD number - since BCD is not standardised across different hardware vendors, it seems this particular company is using 1 or more of these 6 unused nibbles as another character...like a decimal point |
| 7 | Your answer then should be a string of length 1000 (998 decimal places...since there's also the "3." characters representing PI |