On 2017-02-19 10:23, Lars Brinkhoff wrote:
Johnny Billquist wrote:
If we're casting votes, I'd put mine on ASCII-ANSI. Because:
- PDP-10 7-bit ASCII files are transformed into 8-bit ASCII files.
- It's simple.
- Words are always encoded into 5 octets.
With one bit lost... (7*5 == 35)
Maybe I'm missing the point here, but if you want to handle anything
except 7bit text, then I think this format would fail...
The format I've seen called ANSI-ASCII does handle the last bit. It
puts it at the top of the last octet.
So one 36-bit word AAAAAAABBBBBBBCCCCCCCDDDDDDDEEEEEEEF becomes the five
octets 0AAAAAAA 0BBBBBBB CCCCCCC 0DDDDDDD FEEEEEEE.
I think you forgot one 0 before the Cs. :-)
But ok, such an encoding would work. But then your PDP-10 7-bit ASCII
files might not truly convert into 8-bit ASCII files... That final bit
can be a zero or a one... Some code on a PDP-10 did use that last bit as
well, when playing with 7-bit text, if I remember right.
But I don't know how important you think the property of retaining text
file "compatibility" is.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: [email protected] || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
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