4 ms·
The article explains the choice of 60 bits, which was indeed because of the many factors of 60. "60 is a multiple of 1, 2, 3, 4, 5, and 6. Hence bytes of lengt
by pekim 3y ago
The article explains the choice of 60 bits, which was indeed because of the many factors of 60.
"60 is a multiple of 1, 2, 3, 4, 5, and 6. Hence bytes of length from
1 to 6 bits can be packed efficiently into a 60-bit word without having
to split a byte between one word and the next. If longer bytes were
needed, 60 bits would, of course, no longer be ideal. With present
applications, 1, 4, and 6 bits are the really important cases."
- Karellen 3y ago> If longer bytes were needed, 60 bits would, of course, no longer be ideal. That seems like a weird conclusion for the engineers to come to, because 60 is also a multiple of 10, 12, 15, 20, 30 and (of course) 60 (the complement factors of 1, 2, 3, 4, 5 and 6), so a selection of longer bytes are very obviously available. Given that they balked at the cost of moving up to 64-bit words, I guess moving up to 420-bit computing (for those 7-bit bytes) was out of the question ;-)
- zamadatix 3y agoI think it's more a remark that of the first half dozen byte sizes all six fit evenly but of the next dozen only three do. This makes the divisibility not really hold that much value in the end. Particularly since six bits isn't enough to hold dual case alphanumerics and 3 types of punctuation.
- kristianp 3y agoIt's not a convincing or complete explanation though. Why go so high, when other machines of the time were using 36 bits? And if they saved money by not going up to 64, why not go down to 48 for example?